Chapter 27. Connectors

Table of Contents

27.1. MySQL Connector/ODBC
27.1.1. Connector/ODBC Versions
27.1.2. Connector/ODBC Introduction
27.1.3. Connector/ODBC Installation
27.1.4. Connector/ODBC Configuration
27.1.5. Connector/ODBC Examples
27.1.6. Connector/ODBC Reference
27.1.7. Connector/ODBC Notes and Tips
27.1.8. Connector/ODBC Support
27.2. MySQL Connector/NET
27.2.1. Connector/NET Versions
27.2.2. Connector/NET Installation
27.2.3. Connector/NET Examples and Usage Guide
27.2.4. Connector/NET Reference
27.2.5. Connector/NET Notes and Tips
27.2.6. Connector/NET Support
27.3. MySQL Visual Studio Plugin
27.3.1. Installing the MySQL Visual Studio Plugin
27.3.2. Creating a connection to the MySQL server
27.3.3. Using the MySQL Visual Studio Plugin
27.3.4. Visual Studio Plugin Support
27.4. MySQL Connector/J
27.4.1. Connector/J Versions
27.4.2. Connector/J Installation
27.4.3. Connector/J Examples
27.4.4. Connector/J (JDBC) Reference
27.4.5. Connector/J Notes and Tips
27.4.6. Connector/J Support
27.5. MySQL Connector/MXJ
27.5.1. Connector/MXJ Overview
27.5.2. Connector/MXJ Versions
27.5.3. Connector/MXJ Installation
27.5.4. Connector/MXJ Configuration
27.5.5. Connector/MXJ Reference
27.5.6. Connector/MXJ Notes and Tips
27.5.7. Connector/MXJ Support
27.6. Connector/PHP

This chapter describes MySQL Connectors, drivers that provide connectivity to the MySQL server for client programs. There are currently five MySQL Connectors:

For information on connecting to a MySQL server using other languages and interfaces than those detailed above, including Perl, Python and PHP for other platforms and environments, please refer to the Chapter 26, APIs and Libraries chapter.

27.1. MySQL Connector/ODBC

The MySQL Connector/ODBC is the name for the family of MySQL ODBC drivers (previously called MyODBC drivers) that provide access to a MySQL database using the industry standard Open Database Connectivity (ODBC) API. This reference covers Connector/ODBC 3.51 and Connector/ODBC 5.1. Both releases provide an ODBC compliant interface to MySQL Server.

MySQL Connector/ODBC provides both driver-manager based and native interfaces to the MySQL database, which full support for MySQL functionality, including stored procedures, transactions and, with Connector/ODBC 5.1, full Unicode compliance.

For more information on the ODBC API standard and how to use it, refer to http://support.microsoft.com/kb/110093.

The application development part of this reference assumes a good working knowledge of C, general DBMS knowledge, and finally, but not least, familiarity with MySQL. For more information about MySQL functionality and its syntax, refer to http://dev.mysql.com/doc/.

Typically, you need to install Connector/ODBC only on Windows machines. For Unix and Mac OS X you can use the native MySQL network or named pipe to communicate with your MySQL database. You may need Connector/ODBC for Unix or Mac OS X if you have an application that requires an ODBC interface to communicate with the database. Applications that require ODBC to communicate with MySQL include ColdFusion, Microsoft Office, and Filemaker Pro.

Key topics:

MySQL Enterprise MySQL Enterprise subscribers will find more information about MySQL and ODBC in the Knowledge Base articles about ODBC. Access to the MySQL Knowledge Base collection of articles is one of the advantages of subscribing to MySQL Enterprise. For more information see http://www.mysql.com/products/enterprise/advisors.html.

27.1.1. Connector/ODBC Versions

There are currently two version of Connector/ODBC available:

  • Connector/ODBC 5.1, currently in GA status, is a partial rewrite of the of the 3.51 code base and is designed to work all versions of MySQL from 4.1. Connector/ODBC 5.1 will be a complete implementation of the ODBC Core interface,plus more Level 1 and Level 2 functionality of the ODBC specification than that currently supported by Connector/ODBC 3.51. See Section 27.1.2.1, “Connector/ODBC Roadmap”.

    Connector/ODBC 5.1 also includes the following changes and improvements over the 3.51 release:

    • Improved support on Windows 64-bit platforms.

    • Full Unicode support at the driver level. This includes support for the SQL_WCHAR datatype, and support for Unicode login, password and DSN configurations. For more information,. see Microsoft Knowledgebase Article #716246.

    • Support for the SQL_NUMERIC_STRUCT datatype, which provides easier access to the precise definition of numeric values. For more information, see Microsoft Knowledgebase Article #714556

    • Native Windows setup library. This replaces the Qt library based interface for configuring DSN information within the ODBC Data Sources application.

    • Support for the ODBC descriptor, which improves the handling and metadata of columns and parameter data. For more information, see Microsoft Knowledgebase Article #716339.

  • Connector/ODBC 3.51 is the current release of the 32-bit ODBC driver, also known as the MySQL ODBC 3.51 driver. Connector/ODBC 3.51 has support for ODBC 3.5x specification level 1 (complete core API + level 2 features) in order to continue to provide all functionality of ODBC for accessing MySQL.

The manual for versions of Connector/ODBC older than 3.51 can be located in the corresponding binary or source distribution. Please note that versions of Connector/ODBC earlier than the 3.51 revision were not fully compliant with the ODBC specification.

Note

Development on Connector/ODBC 5.0 was stopped due to development issues. Connector/ODBC 5.1 is now the current development release.

Note

From this section onward, the primary focus of this guide is the Connector/ODBC 3.51 and Connector/ODBC 5.1 drivers.

Note

Version numbers for MySQL products are formatted as X.X.X. However, Windows tools (Control Panel, properties display) may show the version numbers as XX.XX.XX. For example, the official MySQL formatted version number 5.0.9 may be displayed by Windows tools as 5.00.09. The two versions are the same; only the number display format is different.

27.1.2. Connector/ODBC Introduction

ODBC (Open Database Connectivity) provides a way for client programs to access a wide range of databases or data sources. ODBC is a standardized API that allows connections to SQL database servers. It was developed according to the specifications of the SQL Access Group and defines a set of function calls, error codes, and data types that can be used to develop database-independent applications. ODBC usually is used when database independence or simultaneous access to different data sources is required.

For more information about ODBC, refer to http://support.microsoft.com/kb/110093.

27.1.2.1. Connector/ODBC Roadmap

Connector/ODBC 5.1 is currently in development and will be a complete implementation of the ODBC Core interface,plus more Level 1 and Level 2 functionality of the ODBC specification than that currently supported by Connector/ODBC 3.51.

The following functionality was added or changed as part of 5.1:

The following functionality will be added in a version after 5.1:

27.1.2.2. General Information About ODBC and Connector/ODBC

Open Database Connectivity (ODBC) is a widely accepted application-programming interface (API) for database access. It is based on the Call-Level Interface (CLI) specifications from X/Open and ISO/IEC for database APIs and uses Structured Query Language (SQL) as its database access language.

A survey of ODBC functions supported by Connector/ODBC is given at Section 27.1.6.1, “Connector/ODBC API Reference”. For general information about ODBC, see http://support.microsoft.com/kb/110093.

27.1.2.2.1. Connector/ODBC Architecture

The Connector/ODBC architecture is based on five components, as shown in the following diagram:

Connector/ODBC Architecture
  • Application:

    The Application uses the ODBC API to access the data from the MySQL server. The ODBC API in turn uses the communicates with the Driver Manager. The Application communicates with the Driver Manager using the standard ODBC calls. The Application does not care where the data is stored, how it is stored, or even how the system is configured to access the data. It needs to know only the Data Source Name (DSN).

    A number of tasks are common to all applications, no matter how they use ODBC. These tasks are:

    • Selecting the MySQL server and connecting to it

    • Submitting SQL statements for execution

    • Retrieving results (if any)

    • Processing errors

    • Committing or rolling back the transaction enclosing the SQL statement

    • Disconnecting from the MySQL server

    Because most data access work is done with SQL, the primary tasks for applications that use ODBC are submitting SQL statements and retrieving any results generated by those statements.

  • Driver manager:

    The Driver Manager is a library that manages communication between application and driver or drivers. It performs the following tasks:

    • Resolves Data Source Names (DSN). The DSN is a configuration string that identifies a given database driver, database, database host and optionally authentication information that enables an ODBC application to connect to a database using a standardized reference.

      Because the database connectivity information is identified by the DSN, any ODBC compliant application can connect to the data source using the same DSN reference. This eliminates the need to separately configure each application that needs access to a given database; instead you instruct the application to use a pre-configured DSN.

    • Loading and unloading of the driver required to access a specific database as defined within the DSN. For example, if you have configured a DSN that connects to a MySQL database then the driver manager will load the Connector/ODBC driver to enable the ODBC API to communicate with the MySQL host.

    • Processes ODBC function calls or passes them to the driver for processing.

  • Connector/ODBC Driver:

    The Connector/ODBC driver is a library that implements the functions supported by the ODBC API. It processes ODBC function calls, submits SQL requests to MySQL server, and returns results back to the application. If necessary, the driver modifies an application's request so that the request conforms to syntax supported by MySQL.

  • DSN Configuration:

    The ODBC configuration file stores the driver and database information required to connect to the server. It is used by the Driver Manager to determine which driver to be loaded according to the definition in the DSN. The driver uses this to read connection parameters based on the DSN specified. For more information, Section 27.1.4, “Connector/ODBC Configuration”.

  • MySQL Server:

    The MySQL database where the information is stored. The database is used as the source of the data (during queries) and the destination for data (during inserts and updates).

27.1.2.2.2. ODBC Driver Managers

An ODBC Driver Manager is a library that manages communication between the ODBC-aware application and any drivers. Its main functionality includes:

  • Resolving Data Source Names (DSN).

  • Driver loading and unloading.

  • Processing ODBC function calls or passing them to the driver.

Both Windows and Mac OS X include ODBC driver managers with the operating system. Most ODBC Driver Manager implementations also include an administration application that makes the configuration of DSN and drivers easier. Examples and information on these managers, including Unix ODBC driver managers are listed below:

  • Microsoft Windows ODBC Driver Manager (odbc32.dll), http://support.microsoft.com/kb/110093.

  • Mac OS X includes ODBC Administrator, a GUI application that provides a simpler configuration mechanism for the Unix iODBC Driver Manager. You can configure DSN and driver information either through ODBC Administrator or through the iODBC configuration files. This also means that you can test ODBC Administrator configurations using the iodbctest command. http://www.apple.com.

  • unixODBC Driver Manager for Unix (libodbc.so). See http://www.unixodbc.org, for more information. The unixODBC Driver Manager includes the Connector/ODBC driver 3.51 in the installation package, starting with version unixODBC 2.1.2.

  • iODBC ODBC Driver Manager for Unix (libiodbc.so), see http://www.iodbc.org, for more information.

27.1.3. Connector/ODBC Installation

You can install the Connector/ODBC drivers using two different methods, a binary installation and a source installation. The binary installation is the easiest and most straightforward method of installation. Using the source installation methods should only be necessary on platforms where a binary installation package is not available, or in situations where you want to customize or modify the installation process or Connector/ODBC drivers before installation.

Where to Get Connector/ODBC

MySQL AB distributes all its products under the General Public License (GPL). You can get a copy of the latest version of Connector/ODBC binaries and sources from the MySQL AB Web site http://dev.mysql.com/downloads/.

For more information about Connector/ODBC, visit http://www.mysql.com/products/myodbc/.

For more information about licensing, visit http://www.mysql.com/company/legal/licensing/.

Supported Platforms

Connector/ODBC can be used on all major platforms supported by MySQL. You can install it on:

  • Windows 95, 98, Me, NT, 2000, XP, and 2003

  • All Unix-like Operating Systems, including: AIX, Amiga, BSDI, DEC, FreeBSD, HP-UX 10/11, Linux, NetBSD, OpenBSD, OS/2, SGI Irix, Solaris, SunOS, SCO OpenServer, SCO UnixWare, Tru64 Unix

  • Mac OS X and Mac OS X Server

Using a binary distribution offers the most straightforward method for installing Connector/ODBC. If you want more control over the driver, the installation location and or to customize elements of the driver you will need to build and install from the source.

If a binary distribution is not available for a particular platform build the driver from the original source code. You can contribute the binaries you create to MySQL by sending a mail message to , so that it becomes available for other users.

For further instructions:

27.1.3.1. Installing Connector/ODBC from a Binary Distribution on Windows

Before installing the Connector/ODBC drivers on Windows you should ensure that your Microsoft Data Access Components (MDAC) are up to date. You can obtain the latest version from the Microsoft Data Access and Storage Web site.

There are three available distribution types to use when installing for Windows. The contents in each case are identical, it is only the installation method which is different.

Note

An OLEDB/ODBC driver for Windows 64-bit is available from Microsoft Downloads.

27.1.3.1.1. Installing the Windows Connector/ODBC Driver using an installer

The installer packages offer a very simple method for installing the Connector/ODBC drivers. If you have downloaded the zipped installer then you must extract the installer application. The basic installation process is identical for both installers.

You should follow these steps to complete the installation:

  1. Double click on the standalone installer that you extracted, or the MSI file you downloaded.

  2. The MySQL Connector/ODBC 3.51 - Setup Wizard will start. Click the Next button to begin the installation process.

    Connector/ODBC Windows Installer -
                Welcome
  3. You will need to choose the installation type. The Typical installation provides the standard files you will need to connect to a MySQL database using ODBC. The Complete option installs all the available files, including debug and utility components. It is recommended you choose one of these two options to complete the installation. If choose one of these methods, click Next and then proceed to step 5.

    You may also choose a Custom installation, which enables you to select the individual components that you want to install. You have chosen this method, click Next and then proceed to step 4.

    Connector/ODBC Windows Installer -
                Choosing a Setup type welcome
  4. If you have chosen a custom installation, use the pop-ups to select which components to install and then click Next to install the necessary files.

    Connector/ODBC Windows Installer -
                Custom Installation welcome
  5. Once the files have copied to your machine, the installation is complete. Click Finish to exit the installer.

    Connector/ODBC Windows Installer -
                Completion welcome

Now the installation is complete, you can continue to configure your ODBC connections using Section 27.1.4, “Connector/ODBC Configuration”.

27.1.3.1.2. Installing the Windows Connector/ODBC Driver using the Zipped DLL package

If you have downloaded the Zipped DLL package then you must install the individual files required for Connector/ODBC operation manually. Once you have unzipped the installation files, you can either perform this operation by hand, executing each statement individually, or you can use the included Batch file to perform an installation to the default locations.

To install using the Batch file:

  1. Unzip the Connector/ODBC Zipped DLL package.

  2. Open a Command Prompt.

  3. Change to the directory created when you unzipped the Connector/ODBC Zipped DLL package.

  4. Run Install.bat:

    C:\> Install.bat

    This will copy the necessary files into the default location, and then register the Connector/ODBC driver with the Windows ODBC manager.

If you want to copy the files to an alternative location - for example, to run or test different versions of the Connector/ODBC driver on the same machine, then you must copy the files by hand. It is however not recommended to install these files in a non-standard location. To copy the files by hand to the default installation location use the following steps:

  1. Unzip the Connector/ODBC Zipped DLL package.

  2. Open a Command Prompt.

  3. Change to the directory created when you unzipped the Connector/ODBC Zipped DLL package.

  4. Copy the library files to a suitable directory. The default is to copy them into the default Windows system directory \Windows\System32:

    C:\> copy lib\myodbc3S.dll \Windows\System32
    C:\> copy lib\myodbc3S.lib \Windows\System32
    C:\> copy lib\myodbc3.dll \Windows\System32
    C:\> copy lib\myodbc3.lib \Windows\System32
  5. Copy the Connector/ODBC tools. These must be placed into a directory that is in the system PATH. The default is to install these into the Windows system directory \Windows\System32:

    C:\> copy bin\myodbc3i.exe \Windows\System32
    C:\> copy bin\myodbc3m.exe \Windows\System32
    C:\> copy bin\myodbc3c.exe \Windows\System32
  6. Optionally copy the help files. For these files to be accessible through the help system, they must be installed in the Windows system directory:

    C:\> copy doc\*.hlp \Windows\System32
  7. Finally, you must register the Connector/ODBC driver with the ODBC manager:

    C:\> myodbc3i -a -d -t"MySQL ODBC 3.51 Driver;\
      DRIVER=myodbc3.dll;SETUP=myodbc3S.dll"

    You must change the references to the DLL files and command location in the above statement if you have not installed these files into the default location.

27.1.3.2. Installing Connector/ODBC from a Binary Distribution on Unix

There are two methods available for installing Connector/ODBC on Unix from a binary distribution. For most Unix environments you will need to use the tarball distribution. For Linux systems, there is also an RPM distribution available.

27.1.3.2.1. Installing Connector/ODBC from a Binary Tarball Distribution

To install the driver from a tarball distribution (.tar.gz file), download the latest version of the driver for your operating system and follow these steps that demonstrate the process using the Linux version of the tarball:

shell> su root
shell> gunzip mysql-connector-odbc-3.51.11-i686-pc-linux.tar.gz
shell> tar xvf mysql-connector-odbc-3.51.11-i686-pc-linux.tar
shell> cd mysql-connector-odbc-3.51.11-i686-pc-linux

Read the installation instructions in the INSTALL-BINARY file and execute these commands.

shell> cp libmyodbc* /usr/local/lib
shell> cp odbc.ini /usr/local/etc
shell> export ODBCINI=/usr/local/etc/odbc.ini

Then proceed on to Section 27.1.4.5, “Configuring a Connector/ODBC DSN on Unix”, to configure the DSN for Connector/ODBC. For more information, refer to the INSTALL-BINARY file that comes with your distribution.

27.1.3.2.2. Installing Connector/ODBC from an RPM Distribution

To install or upgrade Connector/ODBC from an RPM distribution on Linux, simply download the RPM distribution of the latest version of Connector/ODBC and follow the instructions below. Use su root to become root, then install the RPM file.

If you are installing for the first time:

shell> su root
 shell> rpm -ivh mysql-connector-odbc-3.51.12.i386.rpm

If the driver exists, upgrade it like this:

shell> su root
shell> rpm -Uvh mysql-connector-odbc-3.51.12.i386.rpm

If there is any dependency error for MySQL client library, libmysqlclient, simply ignore it by supplying the --nodeps option, and then make sure the MySQL client shared library is in the path or set through LD_LIBRARY_PATH.

This installs the driver libraries and related documents to /usr/local/lib and /usr/share/doc/MyODBC, respectively. Proceed onto Section 27.1.4.5, “Configuring a Connector/ODBC DSN on Unix”.

To uninstall the driver, become root and execute an rpm command:

shell> su root
shell> rpm -e mysql-connector-odbc

27.1.3.3. Installing Connector/ODBC from a Binary Distribution on Mac OS X

Mac OS X is based on the FreeBSD operating system, and you can normally use the MySQL network port for connecting to MySQL servers on other hosts. Installing the Connector/ODBC driver enables you to connect to MySQL databases on any platform through the ODBC interface. You should only need to install the Connector/ODBC driver when your application requires an ODBC interface. Applications that require or can use ODBC (and therefore the Connector/ODBC driver) include ColdFusion, Filemaker Pro, 4th Dimension and many other applications.

Mac OS X includes its own ODBC manager, based on the iODBC manager. Mac OS X includes an administration tool that provides easier administration of ODBC drivers and configuration, updating the underlying iODBC configuration files.

The method for installing Connector/ODBC on Mac OS X depends on the version on Connector/ODBC you are using. For Connector/ODBC 3.51.14 and later, the package is provided as a compress tar archive that you must manually install. For Connector/ODBC 3.51.13 and earlier the software was provided on a compressed disk image (.dmg) file and included an installer.

In either case, the driver is designed to work with the iODBC driver manager included with Mac OS X.

To install Connector/ODBC 3.51.14 and later:

  1. Download the installation file. Note that versions are available for both PowerPC and Intel platforms.

  2. Extract the archive:

    $ tar zxf mysql-connector-odbc-3.51.16-osx10.4-x86-32bit.tar.gz
  3. The directory created will contain two subdirectories, lib and bin. You need to copy these to a suitable location such as /usr/local:

    $ cp bin/* /usr/local/bin
    $ cp lib/* /usr/local/lib
  4. Finally, you must register the driver with iODBC using the myodbc3i tool you just installed:

    $ myodbc3i -a -d -t"MySQL ODBC 3.51 Driver;Driver=/usr/local/lib/libmyodbc3.so;Setup=/usr/local/lib/libmyodbc3S.so"

You can verify the installed drivers either by using the ODBC Administrator application or the myodbc3i utility:

$ myodbc3i -q -d

To install Connector/ODBC 3.51.13 and earlier, follow these steps:

  1. Download the file to your computer and double-click on the downloaded image file.

  2. Within the disk image you will find an installer package (with the .pkg extension). Double click on this file to start the Mac OS X installer.

  3. You will be presented with the installer welcome message. Click the Continue button to begin the installation process.

    Connector/ODBC Mac OS X Installer -
              Installer welcome
  4. Please take the time to read the Important Information as it contains guidance on how to complete the installation process. Once you have read the notice and collected the necessary information, click Continue.

    Connector/ODBC Mac OS X Installer -
              Important Information
  5. Connector/ODBC drivers are made available under the GNU General Public License. Please read the license if you are not familiar with it before continuing installation. Click Continue to approve the license (you will be asked to confirm that decision) and continue the installation.

    Connector/ODBC Mac OS X Installer -
              License
  6. Choose a location to install the Connector/ODBC drivers and the ODBC Administrator application. You must install the files onto a drive with an operating system and you may be limited in the choices available. Select the drive you want to use, and then click Continue.

    Connector/ODBC Mac OS X Installer -
              Choosing a destination
  7. The installer will automatically select the files that need to be installed on your machine. Click Install to continue. The installer will copy the necessary files to your machine. A progress bar will be shown indicating the installation progress.

    Connector/ODBC Mac OS X Installer -
              Installation type
  8. When installation has been completed you will get a window like the one shown below. Click Close to close and quit the installer.

    Connector/ODBC Mac OS X Installer -
              Installation complete

27.1.3.4. Installing Connector/ODBC from a Source Distribution on Windows

You should only need to install Connector/ODBC from source on Windows if you want to change or modify the source or installation. If you are unsure whether to install from source, please use the binary installation detailed in Section 27.1.3.1, “Installing Connector/ODBC from a Binary Distribution on Windows”.

Installing Connector/ODBC from source on Windows requires a number of different tools and packages:

  • MDAC, Microsoft Data Access SDK from http://support.microsoft.com/kb/110093.

  • Suitable C compiler, such as Microsoft Visual C++ or the C compiler included with Microsoft Visual Studio.

  • Compatible make tool. Microsoft's nmake is used in the examples in this section.

  • MySQL client libraries and include files from MySQL 4.0.0 or higher. (Preferably MySQL 4.0.16 or higher). This is required because Connector/ODBC uses new calls and structures that exist only starting from this version of the library. To get the client libraries and include files, visit http://dev.mysql.com/downloads/.

27.1.3.4.1. Building Connector/ODBC 3.51

Connector/ODBC source distributions include Makefiles that require the nmake or other make utility. In the distribution, you can find Makefile for building the release version and Makefile_debug for building debugging versions of the driver libraries and DLLs.

To build the driver, use this procedure:

  1. Download and extract the sources to a folder, then change directory into that folder. The following command assumes the folder is named myodbc3-src:

    C:\> cd myodbc3-src
    
  2. Edit Makefile to specify the correct path for the MySQL client libraries and header files. Then use the following commands to build and install the release version:

    C:\> nmake -f Makefile
    C:\> nmake -f Makefile install
    

    nmake -f Makefile builds the release version of the driver and places the binaries in subdirectory called Release.

    nmake -f Makefile install installs (copies) the driver DLLs and libraries (myodbc3.dll, myodbc3.lib) to your system directory.

  3. To build the debug version, use Makefile_Debug rather than Makefile, as shown below:

    C:\> nmake -f Makefile_debug
    C:\> nmake -f Makefile_debug install
    
  4. You can clean and rebuild the driver by using:

    C:\> nmake -f Makefile clean
    C:\> nmake -f Makefile install
    

Note

  • Make sure to specify the correct MySQL client libraries and header files path in the Makefiles (set the MYSQL_LIB_PATH and MYSQL_INCLUDE_PATH variables). The default header file path is assumed to be C:\mysql\include. The default library path is assumed to be C:\mysql\lib\opt for release DLLs and C:\mysql\lib\debug for debug versions.

  • For the complete usage of nmake, visit http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dv_vcce4/html/evgrfRunningNMAKE.asp.

  • If you are using the Subversion tree for compiling, all Windows-specific Makefiles are named as Win_Makefile*.

27.1.3.4.2. Testing

After the driver libraries are copied/installed to the system directory, you can test whether the libraries are properly built by using the samples provided in the samples subdirectory:

C:\> cd samples
C:\> nmake -f Makefile all

27.1.3.5. Installing Connector/ODBC from a Source Distribution on Unix

You need the following tools to build MySQL from source on Unix:

  • A working ANSI C++ compiler. gcc 2.95.2 or later, SGI C++, and SunPro C++ are some of the compilers that are known to work.

  • A good make program. GNU make is always recommended and is sometimes required.

  • MySQL client libraries and include files from MySQL 4.0.0 or higher. (Preferably MySQL 4.0.16 or higher). This is required because Connector/ODBC uses new calls and structures that exist only starting from this version of the library. To get the client libraries and include files, visit http://dev.mysql.com/downloads/.

    If you have built your own MySQL server and/or client libraries from source then you must have used the --enable-thread-safe-client option to configure when the libraries were built.

    You should also ensure that the libmysqlclient library were built and installed as a shared library.

  • A compatible ODBC manager must be installed. Connector/ODBC is known to work with the iODBC and unixODBC managers. See Section 27.1.2.2.2, “ODBC Driver Managers”, for more information.

  • If you are using a character set that isn't compiled into the MySQL client library then you need to install the MySQL character definitions from the charsets directory into SHAREDIR (by default, /usr/local/mysql/share/mysql/charsets). These should be in place if you have installed the MySQL server on the same machine. See Section 9.1, “Character Set Support”, for more information on character set support.

Once you have all the required files, unpack the source files to a separate directory, you then have to run configure and build the library using make.

27.1.3.5.1. Typical configure Options

The configure script gives you a great deal of control over how you configure your Connector/ODBC build. Typically you do this using options on the configure command line. You can also affect configure using certain environment variables. For a list of options and environment variables supported by configure, run this command:

shell> ./configure --help

Some of the more commonly used configure options are described here:

  1. To compile Connector/ODBC, you need to supply the MySQL client include and library files path using the --with-mysql-path=DIR option, where DIR is the directory where MySQL is installed.

    MySQL compile options can be determined by running DIR/bin/mysql_config.

  2. Supply the standard header and library files path for your ODBC Driver Manager (iODBC or unixODBC).

    • If you are using iODBC and iODBC is not installed in its default location (/usr/local), you might have to use the --with-iodbc=DIR option, where DIR is the directory where iODBC is installed.

      If the iODBC headers do not reside in DIR/include, you can use the --with-iodbc-includes=INCDIR option to specify their location.

      The applies to libraries. If they are not in DIR/lib, you can use the --with-iodbc-libs=LIBDIR option.

    • If you are using unixODBC, use the --with-unixODBC=DIR option (case sensitive) to make configure look for unixODBC instead of iODBC by default, DIR is the directory where unixODBC is installed.

      If the unixODBC headers and libraries aren't located in DIR/include and DIR/lib, use the --with-unixODBC-includes=INCDIR and --with-unixODBC-libs=LIBDIR options.

  3. You might want to specify an installation prefix other than /usr/local. For example, to install the Connector/ODBC drivers in /usr/local/odbc/lib, use the --prefix=/usr/local/odbc option.

The final configuration command looks something like this:

shell> ./configure --prefix=/usr/local \
         --with-iodbc=/usr/local \
         --with-mysql-path=/usr/local/mysql
27.1.3.5.2. Additional configure Options

There are a number of other options that you need, or want, to set when configuring the Connector/ODBC driver before it is built.

  • To link the driver with MySQL thread safe client libraries libmysqlclient_r.so or libmysqlclient_r.a, you must specify the following configure option:

    --enable-thread-safe
    

    and can be disabled (default) using

    --disable-thread-safe
    

    This option enables the building of the driver thread-safe library libmyodbc3_r.so from by linking with MySQL thread-safe client library libmysqlclient_r.so (The extensions are OS dependent).

    If the compilation with the thread-safe option fails, it may be because the correct thread-libraries on the system could not be located. You should set the value of LIBS to point to the correct thread library for your system.

    LIBS="-lpthread" ./configure ..
    
  • You can enable or disable the shared and static versions of Connector/ODBC using these options:

    --enable-shared[=yes/no]
    --disable-shared
    --enable-static[=yes/no]
    --disable-static
    
  • By default, all the binary distributions are built as non-debugging versions (configured with --without-debug).

    To enable debugging information, build the driver from source distribution and use the --with-debug option when you run configure.

  • This option is available only for source trees that have been obtained from the Subversion repository. This option does not apply to the packaged source distributions.

    By default, the driver is built with the --without-docs option. If you would like the documentation to be built, then execute configure with:

    --with-docs
    
27.1.3.5.3. Building and Compilation

To build the driver libraries, you have to just execute make.

shell> make

If any errors occur, correct them and continue the build process. If you aren't able to build, then send a detailed email to for further assistance.

27.1.3.5.4. Building Shared Libraries

On most platforms, MySQL does not build or support .so (shared) client libraries by default. This is based on our experience of problems when building shared libraries.

In cases like this, you have to download the MySQL distribution and configure it with these options:

--without-server --enable-shared

To build shared driver libraries, you must specify the --enable-shared option for configure. By default, configure does not enable this option.

If you have configured with the --disable-shared option, you can build the .so file from the static libraries using the following commands:

shell> cd mysql-connector-odbc-3.51.01
shell> make
shell> cd driver
shell> CC=/usr/bin/gcc \
          $CC -bundle -flat_namespace -undefined error \
          -o .libs/libmyodbc3-3.51.01.so \
          catalog.o connect.o cursor.o dll.o error.o execute.o \
          handle.o info.o misc.o myodbc3.o options.o prepare.o \
          results.o transact.o utility.o \
          -L/usr/local/mysql/lib/mysql/ \
          -L/usr/local/iodbc/lib/ \
          -lz -lc -lmysqlclient -liodbcinst

Make sure to change -liodbcinst to -lodbcinst if you are using unixODBC instead of iODBC, and configure the library paths accordingly.

This builds and places the libmyodbc3-3.51.01.so file in the .libs directory. Copy this file to the Connector/ODBC library installation directory (/usr/local/lib (or the lib directory under the installation directory that you supplied with the --prefix).

shell> cd .libs
shell> cp libmyodbc3-3.51.01.so /usr/local/lib
shell> cd /usr/local/lib
shell> ln -s libmyodbc3-3.51.01.so libmyodbc3.so

To build the thread-safe driver library:

shell> CC=/usr/bin/gcc \
          $CC -bundle -flat_namespace -undefined error
          -o .libs/libmyodbc3_r-3.51.01.so
          catalog.o connect.o cursor.o dll.o error.o execute.o
          handle.o info.o misc.o myodbc3.o options.o prepare.o
          results.o transact.o utility.o
          -L/usr/local/mysql/lib/mysql/
          -L/usr/local/iodbc/lib/
          -lz -lc -lmysqlclient_r -liodbcinst
27.1.3.5.5. Installing Driver Libraries

To install the driver libraries, execute the following command:

shell> make install

That command installs one of the following sets of libraries:

For Connector/ODBC 3.51:

  • libmyodbc3.so

  • libmyodbc3-3.51.01.so, where 3.51.01 is the version of the driver

  • libmyodbc3.a

For thread-safe Connector/ODBC 3.51:

  • libmyodbc3_r.so

  • libmyodbc3-3_r.51.01.so

  • libmyodbc3_r.a

For more information on build process, refer to the INSTALL file that comes with the source distribution. Note that if you are trying to use the make from Sun, you may end up with errors. On the other hand, GNU gmake should work fine on all platforms.

27.1.3.5.6. Testing Connector/ODBC on Unix

To run the basic samples provided in the distribution with the libraries that you built, use the following command:

shell> make test

Before running the tests, create the DSN 'myodbc3' in odbc.ini and set the environment variable ODBCINI to the correct odbc.ini file; and MySQL server is running. You can find a sample odbc.ini with the driver distribution.

You can even modify the samples/run-samples script to pass the desired DSN, UID, and PASSWORD values as the command-line arguments to each sample.

27.1.3.5.7. Building Connector/ODBC from Source on Mac OS X

To build the driver on Mac OS X (Darwin), make use of the following configure example:

shell> ./configure --prefix=/usr/local
          --with-unixODBC=/usr/local
          --with-mysql-path=/usr/local/mysql
          --disable-shared
          --enable-gui=no
          --host=powerpc-apple

The command assumes that the unixODBC and MySQL are installed in the default locations. If not, configure accordingly.

On Mac OS X, --enable-shared builds .dylib files by default. You can build .so files like this:

shell> make
shell> cd driver
shell> CC=/usr/bin/gcc \
          $CC -bundle -flat_namespace -undefined error
          -o .libs/libmyodbc3-3.51.01.so *.o
          -L/usr/local/mysql/lib/
          -L/usr/local/iodbc/lib
          -liodbcinst -lmysqlclient -lz -lc

To build the thread-safe driver library:

shell> CC=/usr/bin/gcc \
          $CC -bundle -flat_namespace -undefined error
          -o .libs/libmyodbc3-3.51.01.so *.o
          -L/usr/local/mysql/lib/
          -L/usr/local/iodbc/lib
          -liodbcinst -lmysqlclienti_r -lz -lc -lpthread

Make sure to change the -liodbcinst to -lodbcinst in case of using unixODBC instead of iODBC and configure the libraries path accordingly.

In Apple's version of GCC, both cc and gcc are actually symbolic links to gcc3.

Copy this library to the $prefix/lib directory and symlink to libmyodbc3.so.

You can cross-check the output shared-library properties using this command:

shell> otool -LD .libs/libmyodbc3-3.51.01.so
27.1.3.5.8. Building Connector/ODBC from Source on HP-UX

To build the driver on HP-UX 10.x or 11.x, make use of the following configure example:

If using cc:

shell> CC="cc" \
          CFLAGS="+z" \
          LDFLAGS="-Wl,+b:-Wl,+s" \
          ./configure --prefix=/usr/local
          --with-unixodbc=/usr/local
          --with-mysql-path=/usr/local/mysql/lib/mysql
          --enable-shared
          --enable-thread-safe

If using gcc:

shell> CC="gcc" \
          LDFLAGS="-Wl,+b:-Wl,+s" \
          ./configure --prefix=/usr/local
          --with-unixodbc=/usr/local
          --with-mysql-path=/usr/local/mysql
          --enable-shared
          --enable-thread-safe

Once the driver is built, cross-check its attributes using chatr .libs/libmyodbc3.sl to determine whether you need to have set the MySQL client library path using the SHLIB_PATH environment variable. For static versions, ignore all shared-library options and run configure with the --disable-shared option.

27.1.3.5.9. Building Connector/ODBC from Source on AIX

To build the driver on AIX, make use of the following configure example:

shell> ./configure --prefix=/usr/local
          --with-unixodbc=/usr/local
          --with-mysql-path=/usr/local/mysql
          --disable-shared
          --enable-thread-safe

Note

For more information about how to build and set up the static and shared libraries across the different platforms refer to ' Using static and shared libraries across platforms'.

27.1.3.6. Installing Connector/ODBC from the Development Source Tree

Caution

You should read this section only if you are interested in helping us test our new code. If you just want to get MySQL Connector/ODBC up and running on your system, you should use a standard release distribution.

To be able to access the Connector/ODBC source tree, you must have Subversion installed. Subversion is freely available from http://subversion.tigris.org/.

To build from the source trees, you need the following tools:

  • autoconf 2.52 (or newer)

  • automake 1.4 (or newer)

  • libtool 1.4 (or newer)

  • m4

The most recent development source tree is available from our public Subversion trees at http://dev.mysql.com/tech-resources/sources.html.

To checkout out the Connector/ODBC sources, change to the directory where you want the copy of the Connector/ODBC tree to be stored, then use the following command:

shell> svn co http://svn.mysql.com/svnpublic/connector-odbc3

You should now have a copy of the entire Connector/ODBC source tree in the directory connector-odbc3. To build from this source tree on Unix or Linux follow these steps:

shell> cd connector-odbc3
shell> aclocal
shell> autoheader
shell> autoconf
shell> automake;
shell> ./configure  # Add your favorite options here
shell> make

For more information on how to build, refer to the INSTALL file located in the same directory. For more information on options to configure, see Section 27.1.3.5.1, “Typical configure Options”

When the build is done, run make install to install the Connector/ODBC 3.51 driver on your system.

If you have gotten to the make stage and the distribution does not compile, please report it to .

On Windows, make use of Windows Makefiles WIN-Makefile and WIN-Makefile_debug in building the driver. For more information, see Section 27.1.3.4, “Installing Connector/ODBC from a Source Distribution on Windows”.

After the initial checkout operation to get the source tree, you should run svn update periodically update your source according to the latest version.

27.1.4. Connector/ODBC Configuration

Before you connect to a MySQL database using the Connector/ODBC driver you must configure an ODBC Data Source Name. The DSN associates the various configuration parameters required to communicate with a database to a specific name. You use the DSN in an application to communicate with the database, rather than specifying individual parameters within the application itself. DSN information can be user specific, system specific, or provided in a special file. ODBC data source names are configured in different ways, depending on your platform and ODBC driver.

27.1.4.1. Data Source Names

A Data Source Name associates the configuration parameters for communicating with a specific database. Generally a DSN consists of the following parameters:

  • Name
  • Hostname
  • Database Name
  • Login
  • Password

In addition, different ODBC drivers, including Connector/ODBC, may accept additional driver-specific options and parameters.

There are three types of DSN:

  • A System DSN is a global DSN definition that is available to any user and application on a particular system. A System DSN can normally only be configured by a systems administrator, or by a user who has specific permissions that let them create System DSNs.

  • A User DSN is specific to an individual user, and can be used to store database connectivity information that the user regularly uses.

  • A File DSN uses a simple file to define the DSN configuration. File DSNs can be shared between users and machines and are therefore more practical when installing or deploying DSN information as part of an application across many machines.

DSN information is stored in different locations depending on your platform and environment.

27.1.4.2. Connector/ODBC Connection Parameters

You can specify the parameters in the following tables for Connector/ODBC when configuring a DSN. Users on Windows can use the Options and Advanced panels when configuring a DSN to set these parameters; see the table for information on which options relate to which fields and checkboxes. On Unix and Mac OS X, use the parameter name and value as the keyword/value pair in the DSN configuration. Alternatively, you can set these parameters within the InConnectionString argument in the SQLDriverConnect() call.

ParameterDefault ValueComment
userODBCThe username used to connect to MySQL.
uidODBCSynonymous with user. Added in 3.51.16.
serverlocalhostThe hostname of the MySQL server.
database The default database.
option0Options that specify how Connector/ODBC should work. See below.
port3306The TCP/IP port to use if server is not localhost.
stmt A statement to execute when connecting to MySQL.
password The password for the user account on server.
pwd Synonymous with password. Added in 3.51.16.
socket The Unix socket file or Windows named pipe to connect to if server is localhost.
sslca The path to a file with a list of trust SSL CAs. Added in 3.51.16.
sslcapath The path to a directory that contains trusted SSL CA certificates in PEM format. Added in 3.51.16.
sslcert The name of the SSL certificate file to use for establishing a secure connection. Added in 3.51.16.
sslcipher A list of allowable ciphers to use for SSL encryption. The cipher list has the same format as the openssl ciphers command Added in 3.51.16.
sslkey The name of the SSL key file to use for establishing a secure connection. Added in 3.51.16.
charset The character set to use for the connection. Added in 3.51.17.
sslverify If set to 1, the SSL certificate will be verified when used with the MySQL connection. If not set, then the default behaviour is to ignore SSL certificate verification.

Note

The SSL configuration parameters can also be automatically loaded from a my.ini or my.cnf file.

The option argument is used to tell Connector/ODBC that the client isn't 100% ODBC compliant. On Windows, you normally select options by toggling the checkboxes in the connection screen, but you can also select them in the option argument. The following options are listed in the order in which they appear in the Connector/ODBC connect screen:

ValueFlagnameGUI OptionDescription
1FLAG_FIELD_LENGTHDon't Optimize Column WidthThe client can't handle that Connector/ODBC returns the real width of a column. This option was removed in 3.51.18.
2FLAG_FOUND_ROWSReturn Matching RowsThe client can't handle that MySQL returns the true value of affected rows. If this flag is set, MySQL returns “found rows” instead. You must have MySQL 3.21.14 or newer to get this to work.
4FLAG_DEBUGTrace Driver Calls To myodbc.logMake a debug log in C:\myodbc.log on Windows, or /tmp/myodbc.log on Unix variants. This option was removed in Connector/ODBC 3.51.18.
8FLAG_BIG_PACKETSAllow Big ResultsDon't set any packet limit for results and bind parameters. Without this option, parameter binding will be truncated to 255 characters.
16FLAG_NO_PROMPTDon't Prompt Upon ConnectDon't prompt for questions even if driver would like to prompt.
32FLAG_DYNAMIC_CURSOREnable Dynamic CursorEnable or disable the dynamic cursor support.
64FLAG_NO_SCHEMAIgnore # in Table NameIgnore use of database name in db_name.tbl_name.col_name.
128FLAG_NO_DEFAULT_CURSORUser Manager CursorsForce use of ODBC manager cursors (experimental).
256FLAG_NO_LOCALEDon't Use Set LocaleDisable the use of extended fetch (experimental).
512FLAG_PAD_SPACEPad Char To Full LengthPad CHAR columns to full column length.
1024FLAG_FULL_COLUMN_NAMESReturn Table Names for SQLDescribeColSQLDescribeCol() returns fully qualified column names.
2048FLAG_COMPRESSED_PROTOUse Compressed ProtocolUse the compressed client/server protocol.
4096FLAG_IGNORE_SPACEIgnore Space After Function NamesTell server to ignore space after function name and before “(” (needed by PowerBuilder). This makes all function names keywords.
8192FLAG_NAMED_PIPEForce Use of Named PipesConnect with named pipes to a mysqld server running on NT.
16384FLAG_NO_BIGINTChange BIGINT Columns to IntChange BIGINT columns to INT columns (some applications can't handle BIGINT).
32768FLAG_NO_CATALOGNo CatalogForces results from the catalog functions, such as SQLTables, to always return NULL and the driver to report that catalogs are not supported.
65536FLAG_USE_MYCNFRead Options From my.cnfRead parameters from the [client] and [odbc] groups from my.cnf.
131072FLAG_SAFESafeAdd some extra safety checks.
262144FLAG_NO_TRANSACTIONSDisable transactionsDisable transactions.
524288FLAG_LOG_QUERYSave queries to myodbc.sqlEnable query logging to c:\myodbc.sql(/tmp/myodbc.sql) file. (Enabled only in debug mode.)
1048576FLAG_NO_CACHEDon't Cache Result (forward only cursors)Do not cache the results locally in the driver, instead read from server (mysql_use_result()). This works only for forward-only cursors. This option is very important in dealing with large tables when you don't want the driver to cache the entire result set.
2097152FLAG_FORWARD_CURSORForce Use Of Forward Only CursorsForce the use of Forward-only cursor type. In case of applications setting the default static/dynamic cursor type, and one wants the driver to use non-cache result sets, then this option ensures the forward-only cursor behavior.
4194304FLAG_AUTO_RECONNECTEnable auto-reconnect.Enables auto-reconnection functionality. You should not use this option with transactions, since a auto reconnection during a incomplete transaction may cause corruption. Note that an auto-reconnected connection will not inherit the same settings and environment as the original. This option was added in Connector/ODBC 3.51.13.
8388608FLAG_AUTO_IS_NULLFlag Auto Is NullWhen set, this option causes the connection to set the SQL_AUTO_IS_NULL option to 1. This disables the standard behavior, but may enable older applications to correctly identify AUTO_INCREMENT values. For more information. See IS NULL. This option was added in Connector/ODBC 3.51.13.
16777216FLAG_ZERO_DATE_TO_MINFlag Zero Date to MinTranslates zero dates (XXXX-00-00) into the minimum date values supported by ODBC, XXXX-01-01. This resolves an issue where some statements will not work because the date returned and the minimum ODBC date value are incompatible. This option was added in Connector/ODBC 3.51.17.
33554432FLAG_MIN_DATE_TO_ZEROFlag Min Date to ZeroTranslates the minimum ODBC date value (XXXX-01-01) to the zero date format supported by MySQL (XXXX-00-00). This resolves an issue where some statements will not work because the date returned and the minimum ODBC date value are incompatible. This option was added in Connector/ODBC 3.51.17.
67108864FLAG_MULTI_STATEMENTSAllow multiple statementsEnables support for batched statements. This option was added in Connector/ODBC 3.51.18.
134217728FLAG_COLUMN_SIZE_S32Limit column size to 32-bit valueLimits the column size to a signed 32-bit value to prevent problems with larger column sizes in applications that do not support them. This option is automatically enabled when working with ADO applications. This option was added in Connector/ODBC 3.51.22.
268435456FLAG_NO_BINARY_RESULTAlways handle binary function results as character dataWhen set this option disables charset 63 for columns with an empty org_table. This option was added in Connector/ODBC 3.51.26.

To select multiple options, add together their values. For example, setting option to 12 (4+8) gives you debugging without packet limits.

The following table shows some recommended option values for various configurations:

ConfigurationOption Value
Microsoft Access, Visual Basic3
Driver trace generation (Debug mode)4
Microsoft Access (with improved DELETE queries)35
Large tables with too many rows2049
Sybase PowerBuilder135168
Query log generation (Debug mode)524288
Generate driver trace as well as query log (Debug mode)524292
Large tables with no-cache results3145731

27.1.4.3. Configuring a Connector/ODBC DSN on Windows

The ODBC Data Source Administrator within Windows enables you to create DSNs, check driver installation and configure ODBC systems such as tracing (used for debugging) and connection pooling.

Different editions and versions of Windows store the ODBC Data Source Administrator in different locations depending on the version of Windows that you are using.

To open the ODBC Data Source Administrator in Windows Server 2003:

Tip

Because it is possible to create DSN using either the 32-bit or 64-bit driver, but using the same DNS identifier, it is advisable to include the driver being used within the DSN identifier. This will help you to identify the DSN when using it from applications such as Excel that are only compatible with the 32-bit driver. For example, you might add Using32bitCODBC to the DSN identifier for the 32-bit interface and Using64bitCODBC for those using the 64-bit Connector/ODBC driver.

  1. On the Start menu, choose Administrative Tools, and then click Data Sources (ODBC).

To open the ODBC Data Source Administrator in Windows 2000 Server or Windows 2000 Professional:

  1. On the Start menu, choose Settings, and then click Control Panel.

  2. In Control Panel, click Administrative Tools.

  3. In Administrative Tools, click Data Sources (ODBC).

To open the ODBC Data Source Administrator on Windows XP:

  1. On the Start menu, click Control Panel.

  2. In the Control Panel when in Category View click Performance and Maintenance and then click Administrative Tools.. If you are viewing the Control Panel in Classic View, click Administrative Tools.

  3. In Administrative Tools, click Data Sources (ODBC).

Irrespective of your Windows version, you should be presented the ODBC Data Source Administrator window:

ODBC Data Source
          Administrator Dialog

Within Windows XP, you can add the Administrative Tools folder to your Start menu to make it easier to locate the ODBC Data Source Administrator. To do this:

  1. Right click on the Start menu.

  2. Select Properties.

  3. Click Customize....

  4. Select the Advanced tab.

  5. Within Start menu items, within the System Administrative Tools section, select Display on the All Programs menu.

Within both Windows Server 2003 and Windows XP you may want to permanently add the ODBC Data Source Administrator to your Start menu. To do this, locate the Data Sources (ODBC) icon using the methods shown, then right-click on the icon and then choose Pin to Start Menu.

The interfaces for the 3.51 and 5.1 versions of the Connector/ODBC driver are different, although the fields and information that you need to enter remain the same.

To configure a DSN using Connector/ODBC 3.51.x or Connector/ODBC 5.1.0, see Section 27.1.4.3.1, “Configuring a Connector/ODBC 3.51 DSN on Windows”.

To configure a DSN using Connector/ODBC 5.1.1 or later, see Section 27.1.4.3.2, “Configuring a Connector/ODBC 5.1 DSN on Windows”.

27.1.4.3.1. Configuring a Connector/ODBC 3.51 DSN on Windows

To add and configure a new Connector/ODBC data source on Windows, use the ODBC Data Source Administrator:

  1. Open the ODBC Data Source Administrator.

  2. To create a System DSN (which will be available to all users) , select the System DSN tab. To create a User DSN, which will be unique only to the current user, click the Add... button.

  3. You will need to select the ODBC driver for this DSN.

    MySQL ODBC Driver
                Selection Dialog

    Select MySQL ODBC 3.51 Driver, then click Finish.

  4. You now need to configure the specific fields for the DSN you are creating through the Add Data Source Name dialog.

    Add Data Source
                Name Dialog for Connector/ODBC 3.51.x

    In the Data Source Name box, enter the name of the data source you want to access. It can be any valid name that you choose.

  5. In the Description box, enter some text to help identify the connection.

  6. In the Server field, enter the name of the MySQL server host that you want to access. By default, it is localhost.

  7. In the User field, enter the user name to use for this connection.

  8. In the Password field, enter the corresponding password for this connection.

  9. The Database pop-up should automatically populate with the list of databases that the user has permissions to access.

  10. Click OK to save the DSN.

A completed DSN configuration may look like this:

SampleMySQL ODBC DSN
            Configuration Dialog

You can verify the connection using the parameters you have entered by clicking the Test button. If the connection could be made successfully, you will be notified with a Success; connection was made! dialog.

If the connection failed, you can obtain more information on the test and why it may have failed by clicking the Diagnostics... button to show additional error messages.

You can configure a number of options for a specific DSN by using either the Connect Options or Advanced tabs in the DSN configuration dialog.

Connector/ODBC Connect Options
            Dialog

The three options you can configure are:

  • Port sets the TCP/IP port number to use when communicating with MySQL. Communication with MySQL uses port 3306 by default. If your server is configured to use a different TCP/IP port, you must specify that port number here.

  • Socket sets the name or location of a specific socket or Windows pipe to use when communicating with MySQL.

  • Initial Statement defines an SQL statement that will be executed when the connection to MySQL is opened. You can use this to set MySQL options for your connection, such as disabling autocommit.

  • Character Set is a pop-up list from which you can select the default character set to be used with this connection. The Character Set option was added in 3.5.17.

The Advanced tab enables you to configure Connector/ODBC connection parameters. Refer to Section 27.1.4.2, “Connector/ODBC Connection Parameters”, for information about the meaning of these options.

Connector/ODBC Connection Advanced
            Dialog
27.1.4.3.2. Configuring a Connector/ODBC 5.1 DSN on Windows

The DSN configuration when using Connector/ODBC 5.1.1 and later has a slightly different layout. Also, due to the native Unicode support within Connector/ODBC 5.1, you no longer need to specify the initial character set to be used with your connection.

To configure a DSN using the Connector/ODBC 5.1.1 or later driver:

  1. Open the ODBC Data Source Administrator.

  2. To create a System DSN (which will be available to all users) , select the System DSN tab. To create a User DSN, which will be unique only to the current user, click the Add... button.

  3. You will need to select the ODBC driver for this DSN.

    MySQL ODBC Driver
                Selection Dialog

    Select MySQL ODBC 5.1 Driver, then click Finish.

  4. You now need to configure the specific fields for the DSN you are creating through the Connection Parameters dialog.

    Add Data Source
                Name Dialog for Connector/ODBC 5.1

    In the Data Source Name box, enter the name of the data source you want to access. It can be any valid name that you choose.

  5. In the Description box, enter some text to help identify the connection.

  6. In the Server field, enter the name of the MySQL server host that you want to access. By default, it is localhost.

  7. In the User field, enter the user name to use for this connection.

  8. In the Password field, enter the corresponding password for this connection.

  9. The Database pop-up should automatically populate with the list of databases that the user has permissions to access.

  10. To communicate over a different TCP/IP port than the default (3306), change the value of the Port.

  11. Click OK to save the DSN.

You can verify the connection using the parameters you have entered by clicking the Test button. If the connection could be made successfully, you will be notified with a Success; connection was made! dialog.

You can configure a number of options for a specific DSN by using the Details button.

Connector/ODBC Connect Options
            Dialog

The Details button opens a tabbed display which allows you to set additional options:

  • Flags 1, Flags 2, and Flags 3 enable you to select the additional flags for the DSN connection. For more information on these flags, see Section 27.1.4.2, “Connector/ODBC Connection Parameters”.

  • Debug allows you to enable ODBC debugging to record the queries you execute through the DSN to the myodbc.sql file. For more information, see Section 27.1.4.8, “Getting an ODBC Trace File”.

  • SSL Settings configures the additional options required for using the Secure Sockets Layer (SSL) when communicating with MySQL server. Note that you must have enabled SSL and configured the MySQL server with suitable certificates to communicate over SSL.

    Connector/ODBC 5.1 SSL
                Configuration

The Advanced tab enables you to configure Connector/ODBC connection parameters. Refer to Section 27.1.4.2, “Connector/ODBC Connection Parameters”, for information about the meaning of these options.

27.1.4.3.3. Errors and Debugging

This section answers Connector/ODBC connection-related questions.

  • While configuring a Connector/ODBC DSN, a Could Not Load Translator or Setup Library error occurs

    For more information, refer to MS KnowledgeBase Article(Q260558). Also, make sure you have the latest valid ctl3d32.dll in your system directory.

  • On Windows, the default myodbc3.dll is compiled for optimal performance. If you want to debug Connector/ODBC 3.51 (for example, to enable tracing), you should instead use myodbc3d.dll. To install this file, copy myodbc3d.dll over the installed myodbc3.dll file. Make sure to revert back to the release version of the driver DLL once you are done with the debugging because the debug version may cause performance issues. Note that the myodbc3d.dll isn't included in Connector/ODBC 3.51.07 through 3.51.11. If you are using one of these versions, you should copy that DLL from a previous version (for example, 3.51.06).

27.1.4.4. Configuring a Connector/ODBC DSN on Mac OS X

To configure a DSN on Mac OS X you can either use the myodbc3i utility, edit the odbc.ini file within the Library/ODBC directory of the user or the should use the ODBC Administrator. If you have Mac OS X 10.2 or earlier, refer to Section 27.1.4.5, “Configuring a Connector/ODBC DSN on Unix”. Select whether you want to create a User DSN or a System DSN. If you want to add a System DSN, you may need to authenticate with the system. You must click the padlock and enter a user and password with administrator privileges.

For correct operation of ODBC Administrator, you should ensure that the /Library/ODBC/odbc.ini file used to set up ODBC connectivity and DSNs are writable by the admin group. If this file is not writable by this group then the ODBC Administrator may fail, or may appear to have worked but not generated the correct entry.

Warning

There are known issues with the OS X ODBC Administrator and Connector/ODBC that may prevent you from creating a DSN using this method. In this case you should use the command-line or edit the odbc.ini file directly. Note that existing DSNs or those that you create via the myodbc3i or myodbc-installertool can still be checked and edited using ODBC Administrator.

To create a DSN using the myodbc3i utility, you need only specify the DSN type and the DSN connection string. For example:

$ myodbc3i -a -s -t"DSN=mydb;DRIVER=MySQL ODBC 3.51 Driver;SERVER=mysql;USER=username;PASSWORD=pass"

To use ODBC Administrator:

  1. Open the ODBC Administrator from the Utilities folder in the Applications folder.

    ODBC Administrator Main
              Panel Dialog
  2. On the User DSN or System DSN panel, click Add.

  3. Select the Connector/ODBC driver and click OK.

  4. You will be presented with the Data Source Name dialog. Enter The Data Source Name and an optional Description for the DSN.

    ODBC Administrator Add
                DSN Dialog

  5. Click Add to add a new keyword/value pair to the panel. You should configure at least four pairs to specify the server, username, password and database connection parameters. See Section 27.1.4.2, “Connector/ODBC Connection Parameters”.

  6. Click OK to add the DSN to the list of configured data source names.

A completed DSN configuration may look like this:

ODBC Administrator Sample
          DSN Dialog

You can configure additional ODBC options to your DSN by adding further keyword/value pairs and setting the corresponding values. See Section 27.1.4.2, “Connector/ODBC Connection Parameters”.

27.1.4.5. Configuring a Connector/ODBC DSN on Unix

On Unix, you configure DSN entries directly in the odbc.ini file. Here is a typical odbc.ini file that configures myodbc3 as the DSN name for Connector/ODBC 3.51:

;
;  odbc.ini configuration for Connector/ODBC and Connector/ODBC 3.51 drivers
;

[ODBC Data Sources]
myodbc3     = MyODBC 3.51 Driver DSN

[myodbc3]
Driver       = /usr/local/lib/libmyodbc3.so
Description  = Connector/ODBC 3.51 Driver DSN
SERVER       = localhost
PORT         =
USER         = root
Password     =
Database     = test
OPTION       = 3
SOCKET       =

[Default]
Driver       = /usr/local/lib/libmyodbc3.so
Description  = Connector/ODBC 3.51 Driver DSN
SERVER       = localhost
PORT         =
USER         = root
Password     =
Database     = test
OPTION       = 3
SOCKET       =

Refer to the Section 27.1.4.2, “Connector/ODBC Connection Parameters”, for the list of connection parameters that can be supplied.

Note

If you are using unixODBC, you can use the following tools to set up the DSN:

In some cases when using unixODBC, you might get this error:

Data source name not found and no default driver specified

If this happens, make sure the ODBCINI and ODBCSYSINI environment variables are pointing to the right odbc.ini file. For example, if your odbc.ini file is located in /usr/local/etc, set the environment variables like this:

export ODBCINI=/usr/local/etc/odbc.ini
export ODBCSYSINI=/usr/local/etc

27.1.4.6. Connecting Without a Predefined DSN

You can connect to the MySQL server using SQLDriverConnect, by specifying the DRIVER name field. Here are the connection strings for Connector/ODBC using DSN-Less connections:

For Connector/ODBC 3.51:

ConnectionString = "DRIVER={MySQL ODBC 3.51 Driver};\
                   SERVER=localhost;\
                   DATABASE=test;\
                   USER=venu;\
                   PASSWORD=venu;\
                   OPTION=3;"

If your programming language converts backslash followed by whitespace to a space, it is preferable to specify the connection string as a single long string, or to use a concatenation of multiple strings that does not add spaces in between. For example:

ConnectionString = "DRIVER={MySQL ODBC 3.51 Driver};"
                   "SERVER=localhost;"
                   "DATABASE=test;"
                   "USER=venu;"
                   "PASSWORD=venu;"
                   "OPTION=3;"

Note.  Note that on Mac OS X you may need to specify the full path to the Connector/ODBC driver library.

Refer to the Section 27.1.4.2, “Connector/ODBC Connection Parameters”, for the list of connection parameters that can be supplied.

27.1.4.7. ODBC Connection Pooling

Connection pooling enables the ODBC driver to re-use existing connections to a given database from a pool of connections, instead of opening a new connection each time the database is accessed. By enabling connection pooling you can improve the overall performance of your application by lowering the time taken to open a connection to a database in the connection pool.

For more information about connection pooling: http://support.microsoft.com/default.aspx?scid=kb;EN-US;q169470.

27.1.4.8. Getting an ODBC Trace File

If you encounter difficulties or problems with Connector/ODBC, you should start by making a log file from the ODBC Manager and Connector/ODBC. This is called tracing, and is enabled through the ODBC Manager. The procedure for this differs for Windows, Mac OS X and Unix.

27.1.4.8.1. Enabling ODBC Tracing on Windows

To enable the trace option on Windows:

  1. The Tracing tab of the ODBC Data Source Administrator dialog box enables you to configure the way ODBC function calls are traced.

    ODBC Data Source Administrator Tracing
                Dialog
  2. When you activate tracing from the Tracing tab, the Driver Manager logs all ODBC function calls for all subsequently run applications.

  3. ODBC function calls from applications running before tracing is activated are not logged. ODBC function calls are recorded in a log file you specify.

  4. Tracing ceases only after you click Stop Tracing Now. Remember that while tracing is on, the log file continues to increase in size and that tracing affects the performance of all your ODBC applications.

27.1.4.8.2. Enabling ODBC Tracing on Mac OS X

To enable the trace option on Mac OS X 10.3 or later you should use the Tracing tab within ODBC Administrator .

  1. Open the ODBC Administrator.

  2. Select the Tracing tab.

    ODBC Administrator Tracing
                Dialog
  3. Select the Enable Tracing checkbox.

  4. Enter the location where you want to save the Tracing log. If you want to append information to an existing log file, click the Choose... button.

27.1.4.8.3. Enabling ODBC Tracing on Unix

To enable the trace option on Mac OS X 10.2 (or earlier) or Unix you must add the trace option to the ODBC configuration:

  1. On Unix, you need to explicitly set the Trace option in the ODBC.INI file.

    Set the tracing ON or OFF by using TraceFile and Trace parameters in odbc.ini as shown below:

    TraceFile  = /tmp/odbc.trace
    Trace      = 1
    

    TraceFile specifies the name and full path of the trace file and Trace is set to ON or OFF. You can also use 1 or YES for ON and 0 or NO for OFF. If you are using ODBCConfig from unixODBC, then follow the instructions for tracing unixODBC calls at HOWTO-ODBCConfig.

27.1.4.8.4. Enabling a Connector/ODBC Log

To generate a Connector/ODBC log, do the following:

  1. Within Windows, enable the Trace Connector/ODBC option flag in the Connector/ODBC connect/configure screen. The log is written to file C:\myodbc.log. If the trace option is not remembered when you are going back to the above screen, it means that you are not using the myodbcd.dll driver, see Section 27.1.4.3.3, “Errors and Debugging”.

    On Mac OS X, Unix, or if you are using DSN-Less connection, then you need to supply OPTION=4 in the connection string or set the corresponding keyword/value pair in the DSN.

  2. Start your application and try to get it to fail. Then check the Connector/ODBC trace file to find out what could be wrong.

If you need help determining what is wrong, see Section 27.1.8.1, “Connector/ODBC Community Support”.

27.1.5. Connector/ODBC Examples

Once you have configured a DSN to provide access to a database, how you access and use that connection is dependent on the application or programming language. As ODBC is a standardized interface, any application or language that supports ODBC can use the DSN and connect to the configured database.

27.1.5.1. Basic Connector/ODBC Application Steps

Interacting with a MySQL server from an applications using the Connector/ODBC typically involves the following operations:

  • Configure the Connector/ODBC DSN

  • Connect to MySQL server

  • Initialization operations

  • Execute SQL statements

  • Retrieve results

  • Perform Transactions

  • Disconnect from the server

Most applications use some variation of these steps. The basic application steps are shown in the following diagram:

Connector/ODBC Programming
          Flowchart

27.1.5.2. Step-by-step Guide to Connecting to a MySQL Database through Connector/ODBC

A typical installation situation where you would install Connector/ODBC is when you want to access a database on a Linux or Unix host from a Windows machine.

As an example of the process required to set up access between two machines, the steps below take you through the basic steps. These instructions assume that you want to connect to system ALPHA from system BETA with a username and password of myuser and mypassword.

On system ALPHA (the MySQL server) follow these steps:

  1. Start the MySQL server.

  2. Use GRANT to set up an account with a username of myuser that can connect from system BETA using a password of myuser to the database test:

    GRANT ALL ON test.* to 'myuser'@'BETA' IDENTIFIED BY 'mypassword';

    For more information about MySQL privileges, refer to Section 5.5, “MySQL User Account Management”.

On system BETA (the Connector/ODBC client), follow these steps:

  1. Configure a Connector/ODBC DSN using parameters that match the server, database and authentication information that you have just configured on system ALPHA.

    ParameterValueComment
    DSNremote_testA name to identify the connection.
    SERVERALPHAThe address of the remote server.
    DATABASEtestThe name of the default database.
    USERmyuserThe username configured for access to this database.
    PASSWORDmypasswordThe password for myuser.
  2. Using an ODBC-capable application, such as Microsoft Office, connect to the MySQL server using the DSN you have just created. If the connection fails, use tracing to examine the connection process. See Section 27.1.4.8, “Getting an ODBC Trace File”, for more information.

27.1.5.3. Connector/ODBC and Third-Party ODBC Tools

Once you have configured your Connector/ODBC DSN, you can access your MySQL database through any application that supports the ODBC interface, including programming languages and third-party applications. This section contains guides and help on using Connector/ODBC with various ODBC-compatible tools and applications, including Microsoft Word, Microsoft Excel and Adobe/Macromedia ColdFusion.

Connector/ODBC has been tested with the following applications:

PublisherApplicationNotes
AdobeColdFusionFormerly Macromedia ColdFusion
BorlandC++ Builder 
 Builder 4 
 Delphi 
Business ObjectsCrystal Reports 
ClarisFilemaker Pro 
CorelParadox 
Computer AssociatesVisual ObjectsAlso known as CAVO
 AllFusion ERwin Data Modeler 
GuptaTeam DeveloperPreviously known as Centura Team Developer; Gupta SQL/Windows
GensymG2-ODBC Bridge 
InlineiHTML 
LotusNotesVersions 4.5 and 4.6
MicrosoftAccess 
 Excel 
 Visio Enterprise 
 Visual C++ 
 Visual Basic 
 ODBC.NETUsing C#, Visual Basic, C++
 FoxPro 
 Visual Interdev 
OpenOffice.orgOpenOffice.org 
PerlDBD::ODBC 
Pervasive SoftwareDataJunction 
Sambar TechnologiesSambar Server 
SPSSSPSS 
SoftVelocityClarion 
SQLExpressSQLExpress for Xbase++ 
SunStarOffice 
SunSystemsVision 
SybasePowerBuilder 
 PowerDesigner 
theKompany.comData Architect 

If you know of any other applications that work with Connector/ODBC, please send mail to about them.

27.1.5.4. Using Connector/ODBC with Microsoft Access

You can use MySQL database with Microsoft Access using Connector/ODBC. The MySQL database can be used as an import source, an export source, or as a linked table for direct use within an Access application, so you can use Access as the front-end interface to a MySQL database.

27.1.5.4.1. Exporting Access Data to MySQL

To export a table of data from an Access database to MySQL, follow these instructions:

  1. When you open an Access database or an Access project, a Database window appears. It displays shortcuts for creating new database objects and opening existing objects.

    Access Database
  2. Click the name of the table or query you want to export, and then in the File menu, select Export.

  3. In the Export Object Type Object name To dialog box, in the Save As Type box, select ODBC Databases () as shown here:

    Selecting an ODBC Database
  4. In the Export dialog box, enter a name for the file (or use the suggested name), and then select OK.

  5. The Select Data Source dialog box is displayed; it lists the defined data sources for any ODBC drivers installed on your computer. Click either the File Data Source or Machine Data Source tab, and then double-click the Connector/ODBC or Connector/ODBC 3.51 data source that you want to export to. To define a new data source for Connector/ODBC, please Section 27.1.4.3, “Configuring a Connector/ODBC DSN on Windows”.

Note

Ensure that the information that you are exporting to the MySQL table is valid for the corresponding MySQL data types. Values that are outside of the supported range of the MySQL data type but valid within Access may trigger an “overflow” error during the export.

Microsoft Access connects to the MySQL Server through this data source and exports new tables and or data.

27.1.5.4.2. Importing MySQL Data to Access

To import a table or tables from MySQL to Access, follow these instructions:

  1. Open a database, or switch to the Database window for the open database.

  2. To import tables, on the File menu, point to Get External Data, and then click Import.

  3. In the Import dialog box, in the Files Of Type box, select ODBC Databases (). The Select Data Source dialog box lists the defined data sources The Select Data Source dialog box is displayed; it lists the defined data source names.

  4. If the ODBC data source that you selected requires you to log on, enter your login ID and password (additional information might also be required), and then click OK.

  5. Microsoft Access connects to the MySQL server through ODBC data source and displays the list of tables that you can import.

  6. Click each table that you want to import, and then click OK.

27.1.5.4.3. Using Microsoft Access as a Front-end to MySQL

You can use Microsoft Access as a front end to a MySQL database by linking tables within your Microsoft Access database to tables that exist within your MySQL database. When a query is requested on a table within Access, ODBC is used to execute the queries on the MySQL database instead.

To create a linked table:

  1. Open the Access database that you want to link to MySQL.

  2. From the File, choose Get External Data->Link Tables.

    Linking Microsoft Access tables to
                MySQL tables
  3. From the browser, choose ODBC Databases () from the Files of type pop-up.

  4. In the Select Data Source window, choose an existing DSN, either from a File Data Source or Machine Data Source.You can also create a new DSN using the New... button. For more information on creating a DSN see Section 27.1.4.3, “Configuring a Connector/ODBC DSN on Windows”.

    Linking Microsoft Access tables to
                MySQL tables, choosing a DSN
  5. In the Link Tables dialog, select one or more tables from the MySQL database. A link will be created to each table that you select from this list.

    Linking Microsoft Access tables to
                MySQL tables, table selection
  6. If Microsoft Access is unable to determine the unique record identifier for a table automatically then it may ask you to confirm the column, or combination of columns, to be used to uniquely identify each row from the source table. Select the columns you want to use and click OK.

    Linking Microsoft Access tables to
                MySQL tables, choosing unique record identifier

Once the process has been completed, you can now build interfaces and queries to the linked tables just as you would for any Access database.

Use the following procedure to view or to refresh links when the structure or location of a linked table has changed. The Linked Table Manager lists the paths to all currently linked tables.

To view or refresh links:

  1. Open the database that contains links to MySQL tables.

  2. On the Tools menu, point to Add-ins (Database Utilities in Access 2000 or newer), and then click Linked Table Manager.

  3. Select the check box for the tables whose links you want to refresh.

  4. Click OK to refresh the links.

Microsoft Access confirms a successful refresh or, if the table wasn't found, displays the Select New Location of <table name> dialog box in which you can specify its the table's new location. If several selected tables have moved to the new location that you specify, the Linked Table Manager searches that location for all selected tables, and updates all links in one step.

To change the path for a set of linked tables:

  1. Open the database that contains links to tables.

  2. On the Tools menu, point to Add-ins (Database Utilities in Access 2000 or newer), and then click Linked Table Manager.

  3. Select the Always Prompt For A New Location check box.

  4. Select the check box for the tables whose links you want to change, and then click OK.

  5. In the Select New Location of <table name> dialog box, specify the new location, click Open, and then click OK.

27.1.5.5. Using Connector/ODBC with Microsoft Word or Excel

You can use Microsoft Word and Microsoft Excel to access information from a MySQL database using Connector/ODBC. Within Microsoft Word, this facility is most useful when importing data for mailmerge, or for tables and data to be included in reports. Within Microsoft Excel, you can execute queries on your MySQL server and import the data directly into an Excel Worksheet, presenting the data as a series of rows and columns.

With both applications, data is accessed and imported into the application using Microsoft Query , which enables you to execute a query though an ODBC source. You use Microsoft Query to build the SQL statement to be executed, selecting the tables, fields, selection criteria and sort order. For example, to insert information from a table in the World test database into an Excel spreadsheet, using the DSN samples shown in Section 27.1.4, “Connector/ODBC Configuration”:

  1. Create a new Worksheet.

  2. From the Data menu, choose Import External Data, and then select New Database Query.

  3. Microsoft Query will start. First, you need to choose the data source, by selecting an existing Data Source Name.

    Microsoft Query, Choose Data
              Source
  4. Within the Query Wizard, you must choose the columns that you want to import. The list of tables available to the user configured through the DSN is shown on the left, the columns that will be added to your query are shown on the right. The columns you choose are equivalent to those in the first section of a SELECT query. Click Next to continue.

    Microsoft Query, Choose Columns
  5. You can filter rows from the query (the equivalent of a WHERE clause) using the Filter Data dialog. Click Next to continue.

    Microsoft Query, Filter Data
  6. Select an (optional) sort order for the data. This is equivalent to using a ORDER BY clause in your SQL query. You can select up to three fields for sorting the information returned by the query. Click Next to continue.

    Microsoft Query, Sort Order
  7. Select the destination for your query. You can select to return the data Microsoft Excel, where you can choose a worksheet and cell where the data will be inserted; you can continue to view the query and results within Microsoft Query, where you can edit the SQL query and further filter and sort the information returned; or you can create an OLAP Cube from the query, which can then be used directly within Microsoft Excel. Click Finish.

    Microsoft Query, Selecting a
              destination

The same process can be used to import data into a Word document, where the data will be inserted as a table. This can be used for mail merge purposes (where the field data is read from a Word table), or where you want to include data and reports within a report or other document.

27.1.5.6. Using Connector/ODBC with Crystal Reports

Crystal Reports can use an ODBC DSN to connect to a database from which you to extract data and information for reporting purposes.

Note

There is a known issue with certain versions of Crystal Reports where the application is unable to open and browse tables and fields through an ODBC connection. Before using Crystal Reports with MySQL, please ensure that you have update to the latest version, including any outstanding service packs and hotfixes. For more information on this issue, see the Business) Objects Knowledgebase for more information.

For example, to create a simple crosstab report within Crystal Reports XI, you should follow these steps:

  1. Create a DSN using the Data Sources (ODBC) tool. You can either specify a complete database, including username and password, or you can build a basic DSN and use Crystal Reports to set the username and password.

    For the purposes of this example, a DSN that provides a connection to an instance of the MySQL Sakila sample database has been created.

  2. Open Crystal Reports and create a new project, or an open an existing reporting project into which you want to insert data from your MySQL data source.

  3. Start the Cross-Tab Report Wizard, either by clicking on the option on the Start Page. Expand the Create New Connection folder, then expand the ODBC (RDO) folder to obtain a list of ODBC data sources.

    You will be asked to select a data source.

    Selecting an Data Source in Crystal
              Reports
  4. When you first expand the ODBC (RDO) folder you will be presented the Data Source Selection screen. From here you can select either a pre-configured DSN, open a file-based DSN or enter and manual connection string. For this example, the Sakila DSN will be used.

    If the DSN contains a username/password combination, or you want to use different authentication credentials, click Next to enter the username and password that you want to use. Otherwise, click Finish to continue the data source selection wizard.

    Selecting an ODBC Data Source in Crystal
              Reports
  5. You will be returned the Cross-Tab Report Creation Wizard. You now need to select the database and tables that you want to include in your report. For our example, we will expand the selected Sakila database. Click the city table and use the > button to add the table to the report. Then repeat the action with the country table. Alternatively you can select multiple tables and add them to the report.

    Finally, you can select the parent Sakila resource and add of the tables to the report.

    Once you have selected the tables you want to include, click Next to continue.

    Selecting an tables in Crystal
              Reports
  6. Crystal Reports will now read the table definitions and automatically identify the links between the tables. The identification of links between tables enables Crystal Reports to automatically lookup and summarize information based on all the tables in the database according to your query. If Crystal Reports is unable to perform the linking itself, you can manually create the links between fields in the tables you have selected.

    Click Next to continue the process.

    Table links/structure in Crystal
              Reports
  7. You can now select the columns and rows that you wish to include within the Cross-Tab report. Drag and drop or use the > buttons to add fields to each area of the report. In the example shown, we will report on cities, organized by country, incorporating a count of the number of cities within each country. If you want to browse the data, select a field and click the Browse Data... button.

    Click Next to create a graph of the results. Since we are not creating a graph from this data, click Finish to generate the report.

    Cross-tab definition in Crystal
              Reports
  8. The finished report will be shown, a sample of the output from the Sakila sample database is shown below.

    Cross-tab final report in Crystal
              Reports

Once the ODBC connection has been opened within Crystal Reports, you can browse and add any fields within the available tables into your reports.

27.1.5.7. Connector/ODBC Programming

With a suitable ODBC Manager and the Connector/ODBC driver installed, any programming language or environment that can support ODBC should be able to connect to a MySQL database through Connector/ODBC.

This includes, but is certainly not limited to, Microsoft support languages (including Visual Basic, C# and interfaces such as ODBC.NET), Perl (through the DBI module, and the DBD::ODBC driver).

27.1.5.7.1. Using Connector/ODBC with Visual Basic Using ADO, DAO and RDO

This section contains simple examples of the use of MySQL ODBC 3.51 Driver with ADO, DAO and RDO.

27.1.5.7.1.1. ADO: rs.addNew, rs.delete, and rs.update

The following ADO (ActiveX Data Objects) example creates a table my_ado and demonstrates the use of rs.addNew, rs.delete, and rs.update.

Private Sub myodbc_ado_Click()

Dim conn As ADODB.Connection
Dim rs As ADODB.Recordset
Dim fld As ADODB.Field
Dim sql As String

'connect to MySQL server using MySQL ODBC 3.51 Driver
Set conn = New ADODB.Connection
conn.ConnectionString = "DRIVER={MySQL ODBC 3.51 Driver};"_
& "SERVER=localhost;"_
& " DATABASE=test;"_
& "UID=venu;PWD=venu; OPTION=3"

conn.Open

'create table
conn.Execute "DROP TABLE IF EXISTS my_ado"
conn.Execute "CREATE TABLE my_ado(id int not null primary key, name varchar(20)," _
& "txt text, dt date, tm time, ts timestamp)"

'direct insert
conn.Execute "INSERT INTO my_ado(id,name,txt) values(1,100,'venu')"
conn.Execute "INSERT INTO my_ado(id,name,txt) values(2,200,'MySQL')"
conn.Execute "INSERT INTO my_ado(id,name,txt) values(3,300,'Delete')"

Set rs = New ADODB.Recordset
rs.CursorLocation = adUseServer

'fetch the initial table ..
rs.Open "SELECT * FROM my_ado", conn
Debug.Print rs.RecordCount
rs.MoveFirst
Debug.Print String(50, "-") & "Initial my_ado Result Set " & String(50, "-")
For Each fld In rs.Fields
Debug.Print fld.Name,
Next
Debug.Print

Do Until rs.EOF
For Each fld In rs.Fields
Debug.Print fld.Value,
Next
rs.MoveNext
Debug.Print
Loop
rs.Close

'rs insert
rs.Open "select * from my_ado", conn, adOpenDynamic, adLockOptimistic
rs.AddNew
rs!Name = "Monty"
rs!txt = "Insert row"
rs.Update
rs.Close

'rs update
rs.Open "SELECT * FROM my_ado"
rs!Name = "update"
rs!txt = "updated-row"
rs.Update
rs.Close

'rs update second time..
rs.Open "SELECT * FROM my_ado"
rs!Name = "update"
rs!txt = "updated-second-time"
rs.Update
rs.Close

'rs delete
rs.Open "SELECT * FROM my_ado"
rs.MoveNext
rs.MoveNext
rs.Delete
rs.Close

'fetch the updated table ..
rs.Open "SELECT * FROM my_ado", conn
Debug.Print rs.RecordCount
rs.MoveFirst
Debug.Print String(50, "-") & "Updated my_ado Result Set " & String(50, "-")
For Each fld In rs.Fields
Debug.Print fld.Name,
Next
Debug.Print

Do Until rs.EOF
For Each fld In rs.Fields
Debug.Print fld.Value,
Next
rs.MoveNext
Debug.Print
Loop
rs.Close
conn.Close
End Sub
27.1.5.7.1.2. DAO: rs.addNew, rs.update, and Scrolling

The following DAO (Data Access Objects) example creates a table my_dao and demonstrates the use of rs.addNew, rs.update, and result set scrolling.

Private Sub myodbc_dao_Click()

Dim ws As Workspace
Dim conn As Connection
Dim queryDef As queryDef
Dim str As String

'connect to MySQL using MySQL ODBC 3.51 Driver
Set ws = DBEngine.CreateWorkspace("", "venu", "venu", dbUseODBC)
str = "odbc;DRIVER={MySQL ODBC 3.51 Driver};"_
& "SERVER=localhost;"_
& " DATABASE=test;"_
& "UID=venu;PWD=venu; OPTION=3"
Set conn = ws.OpenConnection("test", dbDriverNoPrompt, False, str)

'Create table my_dao
Set queryDef = conn.CreateQueryDef("", "drop table if exists my_dao")
queryDef.Execute

Set queryDef = conn.CreateQueryDef("", "create table my_dao(Id INT AUTO_INCREMENT PRIMARY KEY, " _
& "Ts TIMESTAMP(14) NOT NULL, Name varchar(20), Id2 INT)")
queryDef.Execute

'Insert new records using rs.addNew
Set rs = conn.OpenRecordset("my_dao")
Dim i As Integer

For i = 10 To 15
rs.AddNew
rs!Name = "insert record" & i
rs!Id2 = i
rs.Update
Next i
rs.Close

'rs update..
Set rs = conn.OpenRecordset("my_dao")
rs.Edit
rs!Name = "updated-string"
rs.Update
rs.Close

'fetch the table back...
Set rs = conn.OpenRecordset("my_dao", dbOpenDynamic)
str = "Results:"
rs.MoveFirst
While Not rs.EOF
str = " " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2
Debug.Print "DATA:" & str
rs.MoveNext
Wend

'rs Scrolling
rs.MoveFirst
str = " FIRST ROW: " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2
Debug.Print str

rs.MoveLast
str = " LAST ROW: " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2
Debug.Print str

rs.MovePrevious
str = " LAST-1 ROW: " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2
Debug.Print str

'free all resources
rs.Close
queryDef.Close
conn.Close
ws.Close

End Sub
27.1.5.7.1.3. RDO: rs.addNew and rs.update

The following RDO (Remote Data Objects) example creates a table my_rdo and demonstrates the use of rs.addNew and rs.update.

Dim rs As rdoResultset
Dim cn As New rdoConnection
Dim cl As rdoColumn
Dim SQL As String

'cn.Connect = "DSN=test;"
cn.Connect = "DRIVER={MySQL ODBC 3.51 Driver};"_
& "SERVER=localhost;"_
& " DATABASE=test;"_
& "UID=venu;PWD=venu; OPTION=3"

cn.CursorDriver = rdUseOdbc
cn.EstablishConnection rdDriverPrompt


'drop table my_rdo
SQL = "drop table if exists my_rdo"
cn.Execute SQL, rdExecDirect

'create table my_rdo
SQL = "create table my_rdo(id int, name varchar(20))"
cn.Execute SQL, rdExecDirect

'insert - direct
SQL = "insert into my_rdo values (100,'venu')"
cn.Execute SQL, rdExecDirect

SQL = "insert into my_rdo values (200,'MySQL')"
cn.Execute SQL, rdExecDirect

'rs insert
SQL = "select * from my_rdo"
Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect)
rs.AddNew
rs!id = 300
rs!Name = "Insert1"
rs.Update
rs.Close

'rs insert
SQL = "select * from my_rdo"
Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect)
rs.AddNew
rs!id = 400
rs!Name = "Insert 2"
rs.Update
rs.Close

'rs update
SQL = "select * from my_rdo"
Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect)
rs.Edit
rs!id = 999
rs!Name = "updated"
rs.Update
rs.Close

'fetch back...
SQL = "select * from my_rdo"
Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect)
Do Until rs.EOF
For Each cl In rs.rdoColumns
Debug.Print cl.Value,
Next
rs.MoveNext
Debug.Print
Loop
Debug.Print "Row count="; rs.RowCount

'close
rs.Close
cn.Close

End Sub
27.1.5.7.2. Using Connector/ODBC with .NET

This section contains simple examples that demonstrate the use of Connector/ODBC drivers with ODBC.NET.

27.1.5.7.2.1. Using Connector/ODBC with ODBC.NET and C# (C sharp)

The following sample creates a table my_odbc_net and demonstrates its use in C#.

/**
 * @sample    : mycon.cs
 * @purpose   : Demo sample for ODBC.NET using Connector/ODBC
 * @author    : Venu, 
 *
 * (C) Copyright MySQL AB, 1995-2006
 *
 **/
          
/* build command
 *
 *  csc /t:exe
 *      /out:mycon.exe mycon.cs
 *      /r:Microsoft.Data.Odbc.dll
 */
          
using Console = System.Console;
using Microsoft.Data.Odbc;
          
namespace myodbc3
{
  class mycon
  {
    static void Main(string[] args)
    {
      try
        {
          //Connection string for Connector/ODBC 3.51
          string MyConString = "DRIVER={MySQL ODBC 3.51 Driver};" +
            "SERVER=localhost;" +
            "DATABASE=test;" +
            "UID=venu;" +
            "PASSWORD=venu;" +
            "OPTION=3";
          
          //Connect to MySQL using Connector/ODBC
          OdbcConnection MyConnection = new OdbcConnection(MyConString);
          MyConnection.Open();
          
          Console.WriteLine("\n !!! success, connected successfully !!!\n");
          
          //Display connection information
          Console.WriteLine("Connection Information:");
          Console.WriteLine("\tConnection String:" + 
                            MyConnection.ConnectionString);
          Console.WriteLine("\tConnection Timeout:" + 
                            MyConnection.ConnectionTimeout);
          Console.WriteLine("\tDatabase:" + 
                            MyConnection.Database);
          Console.WriteLine("\tDataSource:" + 
                            MyConnection.DataSource);
          Console.WriteLine("\tDriver:" + 
                            MyConnection.Driver);
          Console.WriteLine("\tServerVersion:" + 
                            MyConnection.ServerVersion);
          
          //Create a sample table
          OdbcCommand MyCommand = 
            new OdbcCommand("DROP TABLE IF EXISTS my_odbc_net",
                            MyConnection);
          MyCommand.ExecuteNonQuery();
          MyCommand.CommandText = 
            "CREATE TABLE my_odbc_net(id int, name varchar(20), idb bigint)";
          MyCommand.ExecuteNonQuery();
          
          //Insert
          MyCommand.CommandText = 
            "INSERT INTO my_odbc_net VALUES(10,'venu', 300)";
          Console.WriteLine("INSERT, Total rows affected:" + 
                            MyCommand.ExecuteNonQuery());;
          
          //Insert
          MyCommand.CommandText = 
            "INSERT INTO my_odbc_net VALUES(20,'mysql',400)";
          Console.WriteLine("INSERT, Total rows affected:" + 
                            MyCommand.ExecuteNonQuery());
          
          //Insert
          MyCommand.CommandText = 
            "INSERT INTO my_odbc_net VALUES(20,'mysql',500)";
          Console.WriteLine("INSERT, Total rows affected:" + 
                            MyCommand.ExecuteNonQuery());
          
          //Update
          MyCommand.CommandText = 
            "UPDATE my_odbc_net SET id=999 WHERE id=20";
          Console.WriteLine("Update, Total rows affected:" + 
                            MyCommand.ExecuteNonQuery());
          
          //COUNT(*)
          MyCommand.CommandText = 
            "SELECT COUNT(*) as TRows FROM my_odbc_net";
          Console.WriteLine("Total Rows:" + 
                            MyCommand.ExecuteScalar());
          
          //Fetch
          MyCommand.CommandText = "SELECT * FROM my_odbc_net";
          OdbcDataReader MyDataReader;
          MyDataReader =  MyCommand.ExecuteReader();
          while (MyDataReader.Read())
            {
              if(string.Compare(MyConnection.Driver,"myodbc3.dll") == 0) {
                //Supported only by Connector/ODBC 3.51
                Console.WriteLine("Data:" + MyDataReader.GetInt32(0) + " " +
                                  MyDataReader.GetString(1) + " " +
                                  MyDataReader.GetInt64(2)); 
              }
              else {
                //BIGINTs not supported by Connector/ODBC
                Console.WriteLine("Data:" + MyDataReader.GetInt32(0) + " " +
                                  MyDataReader.GetString(1) + " " +
                                  MyDataReader.GetInt32(2)); 
              }
            }
          
          //Close all resources
          MyDataReader.Close();
          MyConnection.Close();
        }
      catch (OdbcException MyOdbcException) //Catch any ODBC exception ..
        {
          for (int i=0; i < MyOdbcException.Errors.Count; i++)
            {
              Console.Write("ERROR #" + i + "\n" +
                            "Message: " + 
                            MyOdbcException.Errors[i].Message + "\n" +
                            "Native: " + 
                            MyOdbcException.Errors[i].NativeError.ToString() + "\n" +
                            "Source: " + 
                            MyOdbcException.Errors[i].Source + "\n" +
                            "SQL: " + 
                            MyOdbcException.Errors[i].SQLState + "\n");
            }
        }
    }
  }
}
27.1.5.7.2.2. Using Connector/ODBC with ODBC.NET and Visual Basic

The following sample creates a table my_vb_net and demonstrates the use in VB.

' @sample    : myvb.vb
' @purpose   : Demo sample for ODBC.NET using Connector/ODBC
' @author    : Venu, 
'
' (C) Copyright MySQL AB, 1995-2006
'
'

'
' build command
'
' vbc /target:exe
'     /out:myvb.exe
'     /r:Microsoft.Data.Odbc.dll
'     /r:System.dll
'     /r:System.Data.dll
'

Imports Microsoft.Data.Odbc
Imports System

Module myvb
  Sub Main()
    Try

      'Connector/ODBC 3.51 connection string
      Dim MyConString As String = "DRIVER={MySQL ODBC 3.51 Driver};" & _
      "SERVER=localhost;" & _
      "DATABASE=test;" & _
      "UID=venu;" & _
      "PASSWORD=venu;" & _
      "OPTION=3;"

      'Connection
      Dim MyConnection As New OdbcConnection(MyConString)
      MyConnection.Open()

      Console.WriteLine("Connection State::" & MyConnection.State.ToString)

      'Drop
      Console.WriteLine("Dropping table")
      Dim MyCommand As New OdbcCommand()
      MyCommand.Connection = MyConnection
      MyCommand.CommandText = "DROP TABLE IF EXISTS my_vb_net"
      MyCommand.ExecuteNonQuery()

      'Create
      Console.WriteLine("Creating....")
      MyCommand.CommandText = "CREATE TABLE my_vb_net(id int, name varchar(30))"
      MyCommand.ExecuteNonQuery()

      'Insert
      MyCommand.CommandText = "INSERT INTO my_vb_net VALUES(10,'venu')"
      Console.WriteLine("INSERT, Total rows affected:" & _
      MyCommand.ExecuteNonQuery())

      'Insert
      MyCommand.CommandText = "INSERT INTO my_vb_net VALUES(20,'mysql')"
      Console.WriteLine("INSERT, Total rows affected:" & _
      MyCommand.ExecuteNonQuery())

      'Insert
      MyCommand.CommandText = "INSERT INTO my_vb_net VALUES(20,'mysql')"
      Console.WriteLine("INSERT, Total rows affected:" & _
      MyCommand.ExecuteNonQuery())

      'Insert
      MyCommand.CommandText = "INSERT INTO my_vb_net(id) VALUES(30)"
      Console.WriteLine("INSERT, Total rows affected:" & _
                        MyCommand.ExecuteNonQuery())

      'Update
      MyCommand.CommandText = "UPDATE my_vb_net SET id=999 WHERE id=20"
      Console.WriteLine("Update, Total rows affected:" & _
      MyCommand.ExecuteNonQuery())

      'COUNT(*)
      MyCommand.CommandText = "SELECT COUNT(*) as TRows FROM my_vb_net"
      Console.WriteLine("Total Rows:" & MyCommand.ExecuteScalar())

      'Select
      Console.WriteLine("Select * FROM my_vb_net")
      MyCommand.CommandText = "SELECT * FROM my_vb_net"
      Dim MyDataReader As OdbcDataReader
      MyDataReader = MyCommand.ExecuteReader
      While MyDataReader.Read
        If MyDataReader("name") Is DBNull.Value Then
          Console.WriteLine("id = " & _
          CStr(MyDataReader("id")) & "  name = " & _
          "NULL")
        Else
          Console.WriteLine("id = " & _
          CStr(MyDataReader("id")) & "  name = " & _
          CStr(MyDataReader("name")))
        End If
      End While

      'Catch ODBC Exception
    Catch MyOdbcException As OdbcException
      Dim i As Integer
      Console.WriteLine(MyOdbcException.ToString)

      'Catch program exception
    Catch MyException As Exception
      Console.WriteLine(MyException.ToString)
    End Try
  End Sub

27.1.6. Connector/ODBC Reference

This section provides reference material for the Connector/ODBC API, showing supported functions and methods, supported MySQL column types and the corresponding native type in Connector/ODBC, and the error codes returned by Connector/ODBC when a fault occurs.

27.1.6.1. Connector/ODBC API Reference

This section summarizes ODBC routines, categorized by functionality.

For the complete ODBC API reference, please refer to the ODBC Programmer's Reference at http://msdn.microsoft.com/en-us/library/ms714177.aspx.

An application can call SQLGetInfo function to obtain conformance information about Connector/ODBC. To obtain information about support for a specific function in the driver, an application can call SQLGetFunctions.

Note

For backward compatibility, the Connector/ODBC 3.51 driver supports all deprecated functions.

The following tables list Connector/ODBC API calls grouped by task:

Connecting to a data source:

Function nameC/ODBC 3.51StandardPurpose
SQLAllocHandleYesISO 92Obtains an environment, connection, statement, or descriptor handle.
SQLConnectYesISO 92Connects to a specific driver by data source name, user ID, and password.
SQLDriverConnectYesODBCConnects to a specific driver by connection string or requests that the Driver Manager and driver display connection dialog boxes for the user.
SQLAllocEnvYesDeprecatedObtains an environment handle allocated from driver.
SQLAllocConnectYesDeprecatedObtains a connection handle

Obtaining information about a driver and data source:

Function nameC/ODBC 3.51StandardPurpose
SQLDataSourcesNoISO 92Returns the list of available data sources, handled by the Driver Manager
SQLDriversNoODBCReturns the list of installed drivers and their attributes, handles by Driver Manager
SQLGetInfoYesISO 92Returns information about a specific driver and data source.
SQLGetFunctionsYesISO 92Returns supported driver functions.
SQLGetTypeInfoYesISO 92Returns information about supported data types.

Setting and retrieving driver attributes:

Function nameC/ODBC 3.51StandardPurpose
SQLSetConnectAttrYesISO 92Sets a connection attribute.
SQLGetConnectAttrYesISO 92Returns the value of a connection attribute.
SQLSetConnectOptionYesDeprecatedSets a connection option
SQLGetConnectOptionYesDeprecatedReturns the value of a connection option
SQLSetEnvAttrYesISO 92Sets an environment attribute.
SQLGetEnvAttrYesISO 92Returns the value of an environment attribute.
SQLSetStmtAttrYesISO 92Sets a statement attribute.
SQLGetStmtAttrYesISO 92Returns the value of a statement attribute.
SQLSetStmtOptionYesDeprecatedSets a statement option
SQLGetStmtOptionYesDeprecatedReturns the value of a statement option

Preparing SQL requests:

Function nameC/ODBC 3.51StandardPurpose
SQLAllocStmtYesDeprecatedAllocates a statement handle
SQLPrepareYesISO 92Prepares an SQL statement for later execution.
SQLBindParameterYesODBCAssigns storage for a parameter in an SQL statement.
SQLGetCursorNameYesISO 92Returns the cursor name associated with a statement handle.
SQLSetCursorNameYesISO 92Specifies a cursor name.
SQLSetScrollOptionsYesODBCSets options that control cursor behavior.

Submitting requests:

Function nameC/ODBC 3.51StandardPurpose
SQLExecuteYesISO 92Executes a prepared statement.
SQLExecDirectYesISO 92Executes a statement
SQLNativeSqlYesODBCReturns the text of an SQL statement as translated by the driver.
SQLDescribeParamYesODBCReturns the description for a specific parameter in a statement.
SQLNumParamsYesISO 92Returns the number of parameters in a statement.
SQLParamDataYesISO 92Used in conjunction with SQLPutData to supply parameter data at execution time. (Useful for long data values.)
SQLPutDataYesISO 92Sends part or all of a data value for a parameter. (Useful for long data values.)

Retrieving results and information about results:

Function nameC/ODBC 3.51StandardPurpose
SQLRowCountYesISO 92Returns the number of rows affected by an insert, update, or delete request.
SQLNumResultColsYesISO 92Returns the number of columns in the result set.
SQLDescribeColYesISO 92Describes a column in the result set.
SQLColAttributeYesISO 92Describes attributes of a column in the result set.
SQLColAttributesYesDeprecatedDescribes attributes of a column in the result set.
SQLFetchYesISO 92Returns multiple result rows.
SQLFetchScrollYesISO 92Returns scrollable result rows.
SQLExtendedFetchYesDeprecatedReturns scrollable result rows.
SQLSetPosYesODBCPositions a cursor within a fetched block of data and allows an application to refresh data in the rowset or to update or delete data in the result set.
SQLBulkOperationsYesODBCPerforms bulk insertions and bulk bookmark operations, including update, delete, and fetch by bookmark.

Retrieving error or diagnostic information:

Function nameC/ODBC 3.51StandardPurpose
SQLErrorYesDeprecatedReturns additional error or status information
SQLGetDiagFieldYesISO 92Returns additional diagnostic information (a single field of the diagnostic data structure).
SQLGetDiagRecYesISO 92Returns additional diagnostic information (multiple fields of the diagnostic data structure).

Obtaining information about the data source's system tables (catalog functions) item:

Function nameC/ODBC 3.51StandardPurpose
SQLColumnPrivilegesYesODBCReturns a list of columns and associated privileges for one or more tables.
SQLColumnsYesX/OpenReturns the list of column names in specified tables.
SQLForeignKeysYesODBCReturns a list of column names that make up foreign keys, if they exist for a specified table.
SQLPrimaryKeysYesODBCReturns the list of column names that make up the primary key for a table.
SQLSpecialColumnsYesX/OpenReturns information about the optimal set of columns that uniquely identifies a row in a specified table, or the columns that are automatically updated when any value in the row is updated by a transaction.
SQLStatisticsYesISO 92Returns statistics about a single table and the list of indexes associated with the table.
SQLTablePrivilegesYesODBCReturns a list of tables and the privileges associated with each table.
SQLTablesYesX/OpenReturns the list of table names stored in a specific data source.

Performing transactions:

Function nameC/ODBC 3.51StandardPurpose
SQLTransactYesDeprecatedCommits or rolls back a transaction
SQLEndTranYesISO 92Commits or rolls back a transaction.

Terminating a statement:

Function nameC/ODBC 3.51StandardPurpose
SQLFreeStmtYesISO 92Ends statement processing, discards pending results, and, optionally, frees all resources associated with the statement handle.
SQLCloseCursorYesISO 92Closes a cursor that has been opened on a statement handle.
SQLCancelYesISO 92Cancels an SQL statement.

Terminating a connection:

Function nameC/ODBC 3.51StandardPurpose
SQLDisconnectYesISO 92Closes the connection.
SQLFreeHandleYesISO 92Releases an environment, connection, statement, or descriptor handle.
SQLFreeConnectYesDeprecatedReleases connection handle
SQLFreeEnvYesDeprecatedReleases an environment handle

27.1.6.2. Connector/ODBC Data Types

The following table illustrates how driver maps the server data types to default SQL and C data types:

Native ValueSQL TypeC Type
bigint unsignedSQL_BIGINTSQL_C_UBIGINT
bigintSQL_BIGINTSQL_C_SBIGINT
bitSQL_BITSQL_C_BIT
bitSQL_CHARSQL_C_CHAR
blobSQL_LONGVARBINARYSQL_C_BINARY
boolSQL_CHARSQL_C_CHAR
charSQL_CHARSQL_C_CHAR
dateSQL_DATESQL_C_DATE
datetimeSQL_TIMESTAMPSQL_C_TIMESTAMP
decimalSQL_DECIMALSQL_C_CHAR
double precisionSQL_DOUBLESQL_C_DOUBLE
doubleSQL_FLOATSQL_C_DOUBLE
enumSQL_VARCHARSQL_C_CHAR
floatSQL_REALSQL_C_FLOAT
int unsignedSQL_INTEGERSQL_C_ULONG
intSQL_INTEGERSQL_C_SLONG
integer unsignedSQL_INTEGERSQL_C_ULONG
integerSQL_INTEGERSQL_C_SLONG
long varbinarySQL_LONGVARBINARYSQL_C_BINARY
long varcharSQL_LONGVARCHARSQL_C_CHAR
longblobSQL_LONGVARBINARYSQL_C_BINARY
longtextSQL_LONGVARCHARSQL_C_CHAR
mediumblobSQL_LONGVARBINARYSQL_C_BINARY
mediumint unsignedSQL_INTEGERSQL_C_ULONG
mediumintSQL_INTEGERSQL_C_SLONG
mediumtextSQL_LONGVARCHARSQL_C_CHAR
numericSQL_NUMERICSQL_C_CHAR
realSQL_FLOATSQL_C_DOUBLE
setSQL_VARCHARSQL_C_CHAR
smallint unsignedSQL_SMALLINTSQL_C_USHORT
smallintSQL_SMALLINTSQL_C_SSHORT
textSQL_LONGVARCHARSQL_C_CHAR
timeSQL_TIMESQL_C_TIME
timestampSQL_TIMESTAMPSQL_C_TIMESTAMP
tinyblobSQL_LONGVARBINARYSQL_C_BINARY
tinyint unsignedSQL_TINYINTSQL_C_UTINYINT
tinyintSQL_TINYINTSQL_C_STINYINT
tinytextSQL_LONGVARCHARSQL_C_CHAR
varcharSQL_VARCHARSQL_C_CHAR
yearSQL_SMALLINTSQL_C_SHORT

27.1.6.3. Connector/ODBC Error Codes

The following tables lists the error codes returned by the driver apart from the server errors.

Native CodeSQLSTATE 2SQLSTATE 3Error Message
5000100001000General warning
5010100401004String data, right truncated
50201S0201S02Option value changed
50301S0301S03No rows updated/deleted
50401S0401S04More than one row updated/deleted
50501S0601S06Attempt to fetch before the result set returned the first row set
5060700107002SQLBindParameter not used for all parameters
5070700507005Prepared statement not a cursor-specification
5080700907009Invalid descriptor index
5090800208002Connection name in use
5100800308003Connection does not exist
5112400024000Invalid cursor state
5122500025000Invalid transaction state
51325S0125S01Transaction state unknown
5143400034000Invalid cursor name
515S1000HY000General driver defined error
516S1001HY001Memory allocation error
517S1002HY002Invalid column number
518S1003HY003Invalid application buffer type
519S1004HY004Invalid SQL data type
520S1009HY009Invalid use of null pointer
521S1010HY010Function sequence error
522S1011HY011Attribute can not be set now
523S1012HY012Invalid transaction operation code
524S1013HY013Memory management error
525S1015HY015No cursor name available
526S1024HY024Invalid attribute value
527S1090HY090Invalid string or buffer length
528S1091HY091Invalid descriptor field identifier
529S1092HY092Invalid attribute/option identifier
530S1093HY093Invalid parameter number
531S1095HY095Function type out of range
532S1106HY106Fetch type out of range
533S1117HY117Row value out of range
534S1109HY109Invalid cursor position
535S1C00HYC00Optional feature not implemented
021S0121S01Column count does not match value count
02300023000Integrity constraint violation
04200042000Syntax error or access violation
042S0242S02Base table or view not found
042S1242S12Index not found
042S2142S21Column already exists
042S2242S22Column not found
008S0108S01Communication link failure

27.1.7. Connector/ODBC Notes and Tips

Here are some common notes and tips for using Connector/ODBC within different environments, applications and tools. The notes provided here are based on the experiences of Connector/ODBC developers and users.

27.1.7.1. Connector/ODBC General Functionality

This section provides help with common queries and areas of functionality in MySQL and how to use them with Connector/ODBC.

27.1.7.1.1. Obtaining Auto-Increment Values

Obtaining the value of column that uses AUTO_INCREMENT after an INSERT statement can be achieved in a number of different ways. To obtain the value immediately after an INSERT, use a SELECT query with the LAST_INSERT_ID() function.

For example, using Connector/ODBC you would execute two separate statements, the INSERT statement and the SELECT query to obtain the auto-increment value.

INSERT INTO tbl (auto,text) VALUES(NULL,'text');
SELECT LAST_INSERT_ID();

If you do not require the value within your application, but do require the value as part of another INSERT, the entire process can be handled by executing the following statements:

INSERT INTO tbl (auto,text) VALUES(NULL,'text');
INSERT INTO tbl2 (id,text) VALUES(LAST_INSERT_ID(),'text');

Certain ODBC applications (including Delphi and Access) may have trouble obtaining the auto-increment value using the previous examples. In this case, try the following statement as an alternative:

SELECT * FROM tbl WHERE auto IS NULL;

See Section 26.2.14.3, “How to Get the Unique ID for the Last Inserted Row”.

27.1.7.1.2. Dynamic Cursor Support

Support for the dynamic cursor is provided in Connector/ODBC 3.51, but dynamic cursors are not enabled by default. You can enable this function within Windows by selecting the Enable Dynamic Cursor checkbox within the ODBC Data Source Administrator.

On other platforms, you can enable the dynamic cursor by adding 32 to the OPTION value when creating the DSN.

27.1.7.1.3. Connector/ODBC Performance

The Connector/ODBC driver has been optimized to provide very fast performance. If you experience problems with the performance of Connector/ODBC, or notice a large amount of disk activity for simple queries, there are a number of aspects you should check:

  • Ensure that ODBC Tracing is not enabled. With tracing enabled, a lot of information is recorded in the tracing file by the ODBC Manager. You can check, and disable, tracing within Windows using the Tracing panel of the ODBC Data Source Administrator. Within Mac OS X, check the Tracing panel of ODBC Administrator. See Section 27.1.4.8, “Getting an ODBC Trace File”.

  • Make sure you are using the standard version of the driver, and not the debug version. The debug version includes additional checks and reporting measures.

  • Disable the Connector/ODBC driver trace and query logs. These options are enabled for each DSN, so make sure to examine only the DSN that you are using in your application. Within Windows, you can disable the Connector/ODBC and query logs by modifying the DSN configuration. Within Mac OS X and Unix, ensure that the driver trace (option value 4) and query logging (option value 524288) are not enabled.

27.1.7.1.4. Setting ODBC Query Timeout in Windows

For more information on how to set the query timeout on Microsoft Windows when executing queries through an ODBC connection, read the Microsoft knowledgebase document at http://support.microsoft.com/default.aspx?scid=kb%3Ben-us%3B153756.

27.1.7.2. Connector/ODBC Application Specific Tips

Most programs should work with Connector/ODBC, but for each of those listed here, there are specific notes and tips to improve or enhance the way you work with Connector/ODBC and these applications.

With all applications you should ensure that you are using the latest Connector/ODBC drivers, ODBC Manager and any supporting libraries and interfaces used by your application. For example, on Windows, using the latest version of Microsoft Data Access Components (MDAC) will improve the compatibility with ODBC in general, and with the Connector/ODBC driver.

27.1.7.2.1. Using Connector/ODBC with Microsoft Applications

The majority of Microsoft applications have been tested with Connector/ODBC, including Microsoft Office, Microsoft Access and the various programming languages supported within ASP and Microsoft Visual Studio.

27.1.7.2.1.1. Microsoft Access

To improve the integration between Microsoft Access and MySQL through Connector/ODBC:

  • For all versions of Access, you should enable the Connector/ODBC Return matching rows option. For Access 2.0, you should additionally enable the Simulate ODBC 1.0 option.

  • You should have a TIMESTAMP column in all tables that you want to be able to update. For maximum portability, don't use a length specification in the column declaration (which is unsupported within MySQL in versions earlier than 4.1).

  • You should have a primary key in each MySQL table you want to use with Access. If not, new or updated rows may show up as #DELETED#.

  • Use only DOUBLE float fields. Access fails when comparing with single-precision floats. The symptom usually is that new or updated rows may show up as #DELETED# or that you can't find or update rows.

  • If you are using Connector/ODBC to link to a table that has a BIGINT column, the results are displayed as #DELETED#. The work around solution is:

    • Have one more dummy column with TIMESTAMP as the data type.

    • Select the Change BIGINT columns to INT option in the connection dialog in ODBC DSN Administrator.

    • Delete the table link from Access and re-create it.

    Old records may still display as #DELETED#, but newly added/updated records are displayed properly.

  • If you still get the error Another user has changed your data after adding a TIMESTAMP column, the following trick may help you:

    Don't use a table data sheet view. Instead, create a form with the fields you want, and use that form data sheet view. You should set the DefaultValue property for the TIMESTAMP column to NOW(). It may be a good idea to hide the TIMESTAMP column from view so your users are not confused.

  • In some cases, Access may generate SQL statements that MySQL can't understand. You can fix this by selecting "Query|SQLSpecific|Pass-Through" from the Access menu.

  • On Windows NT, Access reports BLOB columns as OLE OBJECTS. If you want to have MEMO columns instead, you should change BLOB columns to TEXT with ALTER TABLE.

  • Access can't always handle the MySQL DATE column properly. If you have a problem with these, change the columns to DATETIME.

  • If you have in Access a column defined as BYTE, Access tries to export this as TINYINT instead of TINYINT UNSIGNED. This gives you problems if you have values larger than 127 in the column.

  • If you have very large (long) tables in Access, it might take a very long time to open them. Or you might run low on virtual memory and eventually get an ODBC Query Failed error and the table cannot open. To deal with this, select the following options:

    • Return Matching Rows (2)

    • Allow BIG Results (8).

    These add up to a value of 10 (OPTION=10).

Some external articles and tips that may be useful when using Access, ODBC and Connector/ODBC:

MySQL Enterprise MySQL Enterprise subscribers will find more information about using ODBC with Access in Knowledge Base articles such as Use MySQL-Specific Syntax with Microsoft Access. To subscribe to MySQL Enterprise see http://www.mysql.com/products/enterprise/advisors.html.

27.1.7.2.1.2. Microsoft Excel and Column Types

If you have problems importing data into Microsoft Excel, particularly numerical, date, and time values, this is probably because of a bug in Excel, where the column type of the source data is used to determine the data type when that data is inserted into a cell within the worksheet. The result is that Excel incorrectly identifies the content and this affects both the display format and the data when it is used within calculations.

To address this issue, use the CONCAT() function in your queries. The use of CONCAT() forces Excel to treat the value as a string, which Excel will then parse and usually correctly identify the embedded information.

However, even with this option, some data may be incorrectly formatted, even though the source data remains unchanged. Use the Format Cells option within Excel to change the format of the displayed information.

27.1.7.2.1.3. Microsoft Visual Basic

To be able to update a table, you must define a primary key for the table.

Visual Basic with ADO can't handle big integers. This means that some queries like SHOW PROCESSLIST do not work properly. The fix is to use OPTION=16384 in the ODBC connect string or to select the Change BIGINT columns to INT option in the Connector/ODBC connect screen. You may also want to select the Return matching rows option.

MySQL Enterprise MySQL Enterprise subscribers can find a discussion about using VBA in the Knowledge Base article, MySQL-Specific Syntax with VBA. To subscribe to MySQL Enterprise see http://www.mysql.com/products/enterprise/advisors.html.

27.1.7.2.1.4. Microsoft Visual InterDev

If you have a BIGINT in your result, you may get the error [Microsoft][ODBC Driver Manager] Driver does not support this parameter. Try selecting the Change BIGINT columns to INT option in the Connector/ODBC connect screen.

27.1.7.2.1.5. Visual Objects

You should select the Don't optimize column widths option.

27.1.7.2.1.6. Microsoft ADO

When you are coding with the ADO API and Connector/ODBC, you need to pay attention to some default properties that aren't supported by the MySQL server. For example, using the CursorLocation Property as adUseServer returns a result of –1 for the RecordCount Property. To have the right value, you need to set this property to adUseClient, as shown in the VB code here:

Dim myconn As New ADODB.Connection
Dim myrs As New Recordset
Dim mySQL As String
Dim myrows As Long

myconn.Open "DSN=MyODBCsample"
mySQL = "SELECT * from user"
myrs.Source = mySQL
Set myrs.ActiveConnection = myconn
myrs.CursorLocation = adUseClient
myrs.Open
myrows = myrs.RecordCount

myrs.Close
myconn.Close

Another workaround is to use a SELECT COUNT(*) statement for a similar query to get the correct row count.

To find the number of rows affected by a specific SQL statement in ADO, use the RecordsAffected property in the ADO execute method. For more information on the usage of execute method, refer to http://msdn.microsoft.com/library/default.asp?url=/library/en-us/ado270/htm/mdmthcnnexecute.asp.

For information, see ActiveX Data Objects(ADO) Frequently Asked Questions.

27.1.7.2.1.7. Using Connector/ODBC with Active Server Pages (ASP)

You should select the Return matching rows option in the DSN.

For more information about how to access MySQL via ASP using Connector/ODBC, refer to the following articles:

A Frequently Asked Questions list for ASP can be found at http://support.microsoft.com/default.aspx?scid=/Support/ActiveServer/faq/data/adofaq.asp.

27.1.7.2.1.8. Using Connector/ODBC with Visual Basic (ADO, DAO and RDO) and ASP

Some articles that may help with Visual Basic and ASP:

27.1.7.2.2. Using Connector/ODBC with Borland Applications

With all Borland applications where the Borland Database Engine (BDE) is used, follow these steps to improve compatibility:

  • Update to BDE 3.2 or newer.

  • Enable the Don't optimize column widths option in the DSN.

  • Enabled the Return matching rows option in the DSN.

27.1.7.2.2.1. Using Connector/ODBC with Borland Builder 4

When you start a query, you can use the Active property or the Open method. Note that Active starts by automatically issuing a SELECT * FROM ... query. That may not be a good thing if your tables are large.

27.1.7.2.2.2. Using Connector/ODBC with Delphi

Also, here is some potentially useful Delphi code that sets up both an ODBC entry and a BDE entry for Connector/ODBC. The BDE entry requires a BDE Alias Editor that is free at a Delphi Super Page near you. (Thanks to Bryan Brunton for this):

fReg:= TRegistry.Create;
fReg.OpenKey('\Software\ODBC\ODBC.INI\DocumentsFab', True);
fReg.WriteString('Database', 'Documents');
fReg.WriteString('Description', ' ');
fReg.WriteString('Driver', 'C:\WINNT\System32\myodbc.dll');
fReg.WriteString('Flag', '1');
fReg.WriteString('Password', '');
fReg.WriteString('Port', ' ');
fReg.WriteString('Server', 'xmark');
fReg.WriteString('User', 'winuser');
fReg.OpenKey('\Software\ODBC\ODBC.INI\ODBC Data Sources', True);
fReg.WriteString('DocumentsFab', 'MySQL');
fReg.CloseKey;
fReg.Free;

Memo1.Lines.Add('DATABASE NAME=');
Memo1.Lines.Add('USER NAME=');
Memo1.Lines.Add('ODBC DSN=DocumentsFab');
Memo1.Lines.Add('OPEN MODE=READ/WRITE');
Memo1.Lines.Add('BATCH COUNT=200');
Memo1.Lines.Add('LANGDRIVER=');
Memo1.Lines.Add('MAX ROWS=-1');
Memo1.Lines.Add('SCHEMA CACHE DIR=');
Memo1.Lines.Add('SCHEMA CACHE SIZE=8');
Memo1.Lines.Add('SCHEMA CACHE TIME=-1');
Memo1.Lines.Add('SQLPASSTHRU MODE=SHARED AUTOCOMMIT');
Memo1.Lines.Add('SQLQRYMODE=');
Memo1.Lines.Add('ENABLE SCHEMA CACHE=FALSE');
Memo1.Lines.Add('ENABLE BCD=FALSE');
Memo1.Lines.Add('ROWSET SIZE=20');
Memo1.Lines.Add('BLOBS TO CACHE=64');
Memo1.Lines.Add('BLOB SIZE=32');

AliasEditor.Add('DocumentsFab','MySQL',Memo1.Lines);
27.1.7.2.2.3. Using Connector/ODBC with C++ Builder

Tested with BDE 3.0. The only known problem is that when the table schema changes, query fields are not updated. BDE, however, does not seem to recognize primary keys, only the index named PRIMARY, although this has not been a problem.

27.1.7.2.3. Using Connector/ODBC with ColdFusion

The following information is taken from the ColdFusion documentation:

Use the following information to configure ColdFusion Server for Linux to use the unixODBC driver with Connector/ODBC for MySQL data sources. You can download Connector/ODBC at http://dev.mysql.com/downloads/connector/odbc/.

ColdFusion version 4.5.1 allows you to us the ColdFusion Administrator to add the MySQL data source. However, the driver is not included with ColdFusion version 4.5.1. Before the MySQL driver appears in the ODBC data sources drop-down list, you must build and copy the Connector/ODBC driver to /opt/coldfusion/lib/libmyodbc.so.

The Contrib directory contains the program mydsn-xxx.zip which allows you to build and remove the DSN registry file for the Connector/ODBC driver on ColdFusion applications.

For more information and guides on using ColdFusion and Connector/ODBC, see the following external sites:

27.1.7.2.4. Using Connector/ODBC with OpenOffice.org

Open Office (http://www.openoffice.org) How-to: MySQL + OpenOffice. How-to: OpenOffice + MyODBC + unixODBC.

27.1.7.2.5. Using Connector/ODBC with Sambar Server

Sambar Server (http://www.sambarserver.info) How-to: MyODBC + SambarServer + MySQL.

27.1.7.2.6. Using Connector/ODBC with Pervasive Software DataJunction

You have to change it to output VARCHAR rather than ENUM, as it exports the latter in a manner that causes MySQL problems.

27.1.7.2.7. Using Connector/ODBC with SunSystems Vision

You should select the Return matching rows option.

27.1.7.3. Connector/ODBC Errors and Resolutions (FAQ)

The following section details some common errors and their suggested fix or alternative solution. If you are still experiencing problems, use the Connector/ODBC mailing list; see Section 27.1.8.1, “Connector/ODBC Community Support”.

Many problems can be resolved by upgrading your Connector/ODBC drivers to the latest available release. On Windows, you should also make sure that you have the latest versions of the Microsoft Data Access Components (MDAC) installed.

Questions

  • 28.1.7.3.1: I have installed Connector/ODBC on Windows XP x64 Edition or Windows Server 2003 R2 x64. The installation completed successfully, but the Connector/ODBC driver does not appear in ODBC Data Source Administrator.

  • 28.1.7.3.2: When connecting or using the Test button in ODBC Data Source Administrator I get error 10061 (Cannot connect to server)

  • 28.1.7.3.3: The following error is reported when using transactions: Transactions are not enabled

  • 28.1.7.3.4: Access reports records as #DELETED# when inserting or updating records in linked tables.

  • 28.1.7.3.5: How do I handle Write Conflicts or Row Location errors?

  • 28.1.7.3.6: Exporting data from Access 97 to MySQL reports a Syntax Error.

  • 28.1.7.3.7: Exporting data from Microsoft DTS to MySQL reports a Syntax Error.

  • 28.1.7.3.8: Using ODBC.NET with Connector/ODBC, while fetching empty string (0 length), it starts giving the SQL_NO_DATA exception.

  • 28.1.7.3.9: Using SELECT COUNT(*) FROM tbl_name within Visual Basic and ASP returns an error.

  • 28.1.7.3.10: Using the AppendChunk() or GetChunk() ADO methods, the Multiple-step operation generated errors. Check each status value error is returned.

  • 28.1.7.3.11: Access Returns Another user had modified the record that you have modified while editing records on a Linked Table.

  • 28.1.7.3.12: When linking an application directly to the Connector/ODBC library under Unix/Linux, the application crashes.

  • 28.1.7.3.13: Applications in the Microsoft Office suite are unable to update tables that have DATE or TIMESTAMP columns.

  • 28.1.7.3.14: When connecting Connector/ODBC 5.x (Beta) to a MySQL 4.x server, the error 1044 Access denied for user 'xxx'@'%' to database 'information_schema' is returned.

  • 28.1.7.3.15: When calling SQLTables, the error S1T00 is returned, but I cannot find this in the list of error numbers for Connector/ODBC.

  • 28.1.7.3.16: When linking to tables in Access 2000 and generating links to tables programmatically, rather than through the table designer interface, you may get errors about tables not existing.

  • 28.1.7.3.17: When I try to use batched statements, the excution of the batched statements fails.

  • 28.1.7.3.18: When connecting to a MySQL server using ADODB and Excel, occasionally the application fails to communicate with the server and the error Got an error reading communication packets appears in the error log.

  • 28.1.7.3.19: When using some applications to access a MySQL server using C/ODBC and outer joins, an error is reported regarding the Outer Join Escape Sequence.

  • 28.1.7.3.20: I can correctly store extended characters in the database (Hebrew/CJK) using C/ODBC 5.1, but when I retrieve the data, the text is not formatted correctly and I get garbled characters.

  • 28.1.7.3.21: I have a duplicate MySQL Connector/ODBC entry within my Installed Programs list, but I cannot delete one of them.

  • 28.1.7.3.22: When submitting queries with parameter binding using UPDATE, my field values are being truncated to 255 characters.

Questions and Answers

28.1.7.3.1: I have installed Connector/ODBC on Windows XP x64 Edition or Windows Server 2003 R2 x64. The installation completed successfully, but the Connector/ODBC driver does not appear in ODBC Data Source Administrator.

This is not a bug, but is related to the way Windows x64 editions operate with the ODBC driver. On Windows x64 editions, the Connector/ODBC driver is installed in the %SystemRoot%\SysWOW64 folder. However, the default ODBC Data Source Administrator that is available through the Administrative Tools or Control Panel in Windows x64 Editions is located in the %SystemRoot%\system32 folder, and only searches this folder for ODBC drivers.

On Windows x64 editions, you should use the ODBC administration tool located at %SystemRoot%\SysWOW64\odbcad32.exe, this will correctly locate the installed Connector/ODBC drivers and enable you to create a Connector/ODBC DSN.

This issue was originally reported as Bug#20301.

28.1.7.3.2: When connecting or using the Test button in ODBC Data Source Administrator I get error 10061 (Cannot connect to server)

This error can be raised by a number of different issues, including server problems, network problems, and firewall and port blocking problems. For more information, see Section B.1.2.2, “Can't connect to [local] MySQL server.

28.1.7.3.3: The following error is reported when using transactions: Transactions are not enabled

This error indicates that you are trying to use transactions with a MySQL table that does not support transactions. Transactions are supported within MySQL when using the InnoDB database engine. In versions of MySQL before Mysql 5.1 you may also use the BDB engine.

You should check the following before continuing:

  • Verify that your MySQL server supports a transactional database engine. Use SHOW ENGINES to obtain a list of the available engine types.

  • Verify that the tables you are updating use a transaction database engine.

  • Ensure that you have not enabled the disable transactions option in your DSN.

28.1.7.3.4: Access reports records as #DELETED# when inserting or updating records in linked tables.

If the inserted or updated records are shown as #DELETED# in the access, then:

  • If you are using Access 2000, you should get and install the newest (version 2.6 or higher) Microsoft MDAC (Microsoft Data Access Components) from http://support.microsoft.com/kb/110093. This fixes a bug in Access that when you export data to MySQL, the table and column names aren't specified.

    You should also get and apply the Microsoft Jet 4.0 Service Pack 5 (SP5) which can be found at http://support.microsoft.com/default.aspx?scid=kb;EN-US;q239114. This fixes some cases where columns are marked as #DELETED# in Access.

  • For all versions of Access, you should enable the Connector/ODBC Return matching rows option. For Access 2.0, you should additionally enable the Simulate ODBC 1.0 option.

  • You should have a timestamp in all tables that you want to be able to update.

  • You should have a primary key in the table. If not, new or updated rows may show up as #DELETED#.

  • Use only DOUBLE float fields. Access fails when comparing with single-precision floats. The symptom usually is that new or updated rows may show up as #DELETED# or that you can't find or update rows.

  • If you are using Connector/ODBC to link to a table that has a BIGINT column, the results are displayed as #DELETED. The work around solution is:

    • Have one more dummy column with TIMESTAMP as the data type.

    • Select the Change BIGINT columns to INT option in the connection dialog in ODBC DSN Administrator.

    • Delete the table link from Access and re-create it.

    Old records still display as #DELETED#, but newly added/updated records are displayed properly.

28.1.7.3.5: How do I handle Write Conflicts or Row Location errors?

If you see the following errors, select the Return Matching Rows option in the DSN configuration dialog, or specify OPTION=2, as the connection parameter:

Write Conflict. Another user has changed your data.

Row cannot be located for updating. Some values may have been changed
since it was last read.

28.1.7.3.6: Exporting data from Access 97 to MySQL reports a Syntax Error.

This error is specific to Access 97 and versions of Connector/ODBC earlier than 3.51.02. Update to the latest version of the Connector/ODBC driver to resolve this problem.

28.1.7.3.7: Exporting data from Microsoft DTS to MySQL reports a Syntax Error.

This error occurs only with MySQL tables using the TEXT or VARCHAR data types. You can fix this error by upgrading your Connector/ODBC driver to version 3.51.02 or higher.

28.1.7.3.8: Using ODBC.NET with Connector/ODBC, while fetching empty string (0 length), it starts giving the SQL_NO_DATA exception.

You can get the patch that addresses this problem from http://support.microsoft.com/default.aspx?scid=kb;EN-US;q319243.

28.1.7.3.9: Using SELECT COUNT(*) FROM tbl_name within Visual Basic and ASP returns an error.

This error occurs because the COUNT(*) expression is returning a BIGINT, and ADO can't make sense of a number this big. Select the Change BIGINT columns to INT option (option value 16384).

28.1.7.3.10: Using the AppendChunk() or GetChunk() ADO methods, the Multiple-step operation generated errors. Check each status value error is returned.

The GetChunk() and AppendChunk() methods from ADO doesn't work as expected when the cursor location is specified as adUseServer. On the other hand, you can overcome this error by using adUseClient.

A simple example can be found from http://www.dwam.net/iishelp/ado/docs/adomth02_4.htm

28.1.7.3.11: Access Returns Another user had modified the record that you have modified while editing records on a Linked Table.

In most cases, this can be solved by doing one of the following things:

  • Add a primary key for the table if one doesn't exist.

  • Add a timestamp column if one doesn't exist.

  • Only use double-precision float fields. Some programs may fail when they compare single-precision floats.

If these strategies don't help, you should start by making a log file from the ODBC manager (the log you get when requesting logs from ODBCADMIN) and a Connector/ODBC log to help you figure out why things go wrong. For instructions, see Section 27.1.4.8, “Getting an ODBC Trace File”.

28.1.7.3.12: When linking an application directly to the Connector/ODBC library under Unix/Linux, the application crashes.

Connector/ODBC 3.51 under Unix/Linux is not compatible with direct application linking. You must use a driver manager, such as iODBC or unixODBC to connect to an ODBC source.

28.1.7.3.13: Applications in the Microsoft Office suite are unable to update tables that have DATE or TIMESTAMP columns.

This is a known issue with Connector/ODBC. You must ensure that the field has a default value (rather than NULL and that the default value is non-zeo (i.e. the default value is not 0000-00-00 00:00:00).

28.1.7.3.14: When connecting Connector/ODBC 5.x (Beta) to a MySQL 4.x server, the error 1044 Access denied for user 'xxx'@'%' to database 'information_schema' is returned.

Connector/ODBC 5.x is designed to work with MySQL 5.0 or later, taking advantage of the INFORMATION_SCHEMA database to determine data definition information. Support for MySQL 4.1 is planned for the final release.

28.1.7.3.15: When calling SQLTables, the error S1T00 is returned, but I cannot find this in the list of error numbers for Connector/ODBC.

The S1T00 error indicates that a general timeout has occurred within the ODBC system and is not a MySQL error. Typically it indicates that the connection you are using is stale, the server is too busy to accept your request or that the server has gone away.

28.1.7.3.16: When linking to tables in Access 2000 and generating links to tables programmatically, rather than through the table designer interface, you may get errors about tables not existing.

There is a known issue with a specific version of the msjet40.dll that exhibits this issue. The version affected is 4.0.9025.0. Reverting to an older version will enable you to create the links. If you have recently updated your version, check your WINDOWS directory for the older version of the file and copy it to the drivers directory.

28.1.7.3.17: When I try to use batched statements, the excution of the batched statements fails.

Batched statement support was added in 3.51.18. Support for batched statements is not enabled by default. You must enable option FLAG_MULTI_STATEMENTS, value 67108864, or select the Allow multiple statements flag within a GUI configuration.

28.1.7.3.18: When connecting to a MySQL server using ADODB and Excel, occasionally the application fails to communicate with the server and the error Got an error reading communication packets appears in the error log.

This error may be related to Keyboard Logger 1.1 from PanteraSoft.com, which is known to interfere with the network communication between MySQL Connector/ODBC and MySQL.

28.1.7.3.19: When using some applications to access a MySQL server using C/ODBC and outer joins, an error is reported regarding the Outer Join Escape Sequence.

This is a known issue with MySQL Connector/ODBC which is not correctly parsing the "Outer Join Escape Sequence", as per the specs at Microsoft ODBC Specs. Currently, Connector/ODBC will return value > 0 when asked for SQL_OJ_CAPABILITIES even though no parsing takes place in the driver to handle the outer join escape sequence.

28.1.7.3.20: I can correctly store extended characters in the database (Hebrew/CJK) using C/ODBC 5.1, but when I retrieve the data, the text is not formatted correctly and I get garbled characters.

When using ASP and UTF8 characters you should add the following to your ASP files to ensure that the data returned is correctly encoded:

Response.CodePage = 65001
Response.CharSet = "utf-8"

28.1.7.3.21: I have a duplicate MySQL Connector/ODBC entry within my Installed Programs list, but I cannot delete one of them.

This problem can occur when you upgrade an existing Connector/ODBC installation, rather than removing and then installing the updated version.

Warning

To fix the problem you should use any working uninstallers to remove existing installations and then may have to edit the contents of the registry. Make sure you have a backup of your registry information before attempting any editing of the registry contents.

28.1.7.3.22: When submitting queries with parameter binding using UPDATE, my field values are being truncated to 255 characters.

You should ensure that the FLAG_BIG_PACKETS option is set for your connection. This removes the 255 character limitation on bound parameters.

27.1.8. Connector/ODBC Support

There are many different places where you can get support for using Connector/ODBC. You should always try the Connector/ODBC Mailing List or Connector/ODBC Forum. See Section 27.1.8.1, “Connector/ODBC Community Support”, for help before reporting a specific bug or issue to MySQL.

27.1.8.1. Connector/ODBC Community Support

MySQL AB provides assistance to the user community by means of its mailing lists. For Connector/ODBC-related issues, you can get help from experienced users by using the mailing list. Archives are available online at http://lists.mysql.com/myodbc.

For information about subscribing to MySQL mailing lists or to browse list archives, visit http://lists.mysql.com/. See Section 1.6.1, “MySQL Mailing Lists”.

Community support from experienced users is also available through the ODBC Forum. You may also find help from other users in the other MySQL Forums, located at http://forums.mysql.com. See Section 1.6.2, “MySQL Community Support at the MySQL Forums”.

27.1.8.2. How to Report Connector/ODBC Problems or Bugs

If you encounter difficulties or problems with Connector/ODBC, you should start by making a log file from the ODBC Manager (the log you get when requesting logs from ODBC ADMIN) and Connector/ODBC. The procedure for doing this is described in Section 27.1.4.8, “Getting an ODBC Trace File”.

Check the Connector/ODBC trace file to find out what could be wrong. You should be able to determine what statements were issued by searching for the string >mysql_real_query in the myodbc.log file.

You should also try issuing the statements from the mysql client program or from admndemo. This helps you determine whether the error is in Connector/ODBC or MySQL.

If you find out something is wrong, please only send the relevant rows (maximum 40 rows) to the myodbc mailing list. See Section 1.6.1, “MySQL Mailing Lists”. Please never send the whole Connector/ODBC or ODBC log file!

You should ideally include the following information with the email:

  • Operating system and version

  • Connector/ODBC version

  • ODBC Driver Manager type and version

  • MySQL server version

  • ODBC trace from Driver Manager

  • Connector/ODBC log file from Connector/ODBC driver

  • Simple reproducible sample

Remember that the more information you can supply to us, the more likely it is that we can fix the problem!

Also, before posting the bug, check the MyODBC mailing list archive at http://lists.mysql.com/myodbc.

If you are unable to find out what's wrong, the last option is to create an archive in tar or Zip format that contains a Connector/ODBC trace file, the ODBC log file, and a README file that explains the problem. You can send this to ftp://ftp.mysql.com/pub/mysql/upload/. Only MySQL engineers have access to the files you upload, and we are very discreet with the data.

If you can create a program that also demonstrates the problem, please include it in the archive as well.

If the program works with another SQL server, you should include an ODBC log file where you perform exactly the same SQL statements so that we can compare the results between the two systems.

Remember that the more information you can supply to us, the more likely it is that we can fix the problem.

27.1.8.3. How to Submit a Connector/ODBC Patch

You can send a patch or suggest a better solution for any existing code or problems by sending a mail message to .

27.1.8.4. Connector/ODBC Change History

The Connector/ODBC Change History (Changelog) is located with the main Changelog for MySQL. See Section E.3, “MySQL Connector/ODBC (MyODBC) Change History”.

27.1.8.5. Credits

These are the developers that have worked on the Connector/ODBC and Connector/ODBC 3.51 Drivers from MySQL AB.

  • Michael (Monty) Widenius

  • Venu Anuganti

  • Peter Harvey

27.2. MySQL Connector/NET

Connector/NET enables developers to easily create .NET applications that require secure, high-performance data connectivity with MySQL. It implements the required ADO.NET interfaces and integrates into ADO.NET aware tools. Developers can build applications using their choice of .NET languages. Connector/NET is a fully managed ADO.NET driver written in 100% pure C#.

Connector/NET includes full support for:

  • MySQL 5.0 features (such as stored procedures)

  • MySQL 4.1 features (server-side prepared statements, Unicode, and shared memory access, and so forth)

  • Large-packet support for sending and receiving rows and BLOBs up to 2 gigabytes in size.

  • Protocol compression which allows for compressing the data stream between the client and server.

  • Support for connecting using TCP/IP sockets, named pipes, or shared memory on Windows.

  • Support for connecting using TCP/IP sockets or Unix sockets on Unix.

  • Support for the Open Source Mono framework developed by Novell.

  • Fully managed, does not utilize the MySQL client library.

This document is intended as a user's guide to Connector/NET and includes a full syntax reference. Syntax information is also included within the Documentation.chm file included with the Connector/NET distribution.

If you are using MySQL 5.0 or later, and Visual Studio as your development environment, you may want also want to use the MySQL Visual Studio Plugin. The plugin acts as a DDEX (Data Designer Extensibility) provider, enabling you to use the data design tools within Visual Studio to manipulate the schema and objects within a MySQL database. For more information, see Section 27.3, “MySQL Visual Studio Plugin”.

Note

Connector/NET 5.1.2 and later include the Visual Studio Plugin by default.

Key topics:

27.2.1. Connector/NET Versions

There are currently three versions of Connector/NET available:

  • Connector/NET 1.0 includes support for MySQL 4.0, and MySQL 5.0 features, and full compatibility with the ADO.NET driver interface.

    Connector/NET 5.0 includes support for MySQL 4.0, MySQL 4.1, MySQL 5.0 and MySQL 5.1 features. Connector/NET 5.0 also includes full support for the ADO.Net 2.0 interfaces and subclasses, includes support for the usage advisor and performance monitor (PerfMon) hooks.

    Connector/NET 5.1 includes support for MySQL 4.0, MySQL 5.0, MySQL 5.1 and MySQL 6.0 (Falcon Preview) features. Connector/NET 5.1 also includes support for a new membership/role provider, Compact Framework 2.0, a new stored procedure parser and improvements to GetSchema. Connector/NET 5.1 also includes the Visual Studio Plugin as a standard installable component.

Note

Version numbers for MySQL products are formatted as X.X.X. However, Windows tools (Control Panel, properties display) may show the version numbers as XX.XX.XX. For example, the official MySQL formatted version number 5.0.9 may be displayed by Windows tools as 5.00.09. The two versions are the same; only the number display format is different.

27.2.2. Connector/NET Installation

Connector/NET runs on any platform that supports the .NET framework. The .NET framework is primarily supported on recent versions of Microsoft Windows, and is supported on Linux through the Open Source Mono framework (see http://www.mono-project.com).

Connector/NET is available for download from http://dev.mysql.com/downloads/connector/net/1.0.html.

27.2.2.1. Installing Connector/NET on Windows

On Windows, installation is supported either through a binary installation process or by downloading a Zip file with the Connector/NET components.

Before installing, you should ensure that your system is up to date, including installing the latest version of the .NET Framework.

27.2.2.1.1. Installing Connector/NET using the Installer

Using the installer is the most straightforward method of installing Connector/NET on Windows and the installed components include the source code, test code and full reference documentation.

Connector/NET is installed through the use of a Windows Installer (.msi) installation package, which can be used to install Connector/NET on all Windows operating systems. The MSI package in contained within a ZIP archive named mysql-connector-net-version.zip, where version indicates the Connector/NET version.

To install Connector/NET:

  1. Double click on the MSI installer file extracted from the Zip you downloaded. Click Next to start the installation.

    Connector/NET Windows Installer -
                Welcome
  2. You must choose the type of installation that you want to perform.

    Connector/NET Windows Installer -
                Installation type

    For most situations, the Typical installation will be suitable. Click the Typical button and proceed to Step 5. A Complete installation installs all the available files. To conduct a Complete installation, click the Complete button and proceed to step 5. If you want to customize your installation, including choosing the components to install and some installation options, click the Custom button and proceed to Step 3.

    The Connector/NET installer will register the connector within the Global Assembly Cache (GAC) - this will make the Connector/NET component available to all applications, not just those where you explicitly reference the Connector/NET component. The installer will also create the necessary links in the Start menu to the documentation and release notes.

  3. If you have chosen a custom installation, you can select the individual components that you want to install, including the core interface component, supporting documentation (a CHM file) samples and examples and the source code. Select the items, and their installation level, and then click Next to continue the installation.

    Note

    For Connector/NET 1.0.8 or lower and Connector 5.0.4 and lower the installer will attempt to install binaries for both 1.x and 2.x of the .NET Framework. If you only have one version of the framework installed, the connector installation may fail. If this happens, you can choose the framework version to be installed through the custom installation step.

    Connector/NET Windows Installer -
                Custom setup
  4. You will be given a final opportunity to confirm the installation. Click Install to copy and install the files onto your machine.

    Connector/NET Windows Installer -
                Confirming installation
  5. Once the installation has been completed, click Finish to exit the installer.

Unless you choose otherwise, Connector/NET is installed in C:\Program Files\MySQL\MySQL Connector Net X.X.X, where X.X.X is replaced with the version of Connector/NET you are installing. New installations do not overwrite existing versions of Connector/NET.

Depending on your installation type, the installed components will include some or all of the following components:

  • bin - Connector/NET MySQL libraries for different versions of the .NET environment.

  • docs - contains a CHM of the Connector/NET documentation.

  • samples - sample code and applications that use the Connector/NET component.

  • src - the source code for the Connector/NET component.

You may also use the /quiet or /q command-line option with the msiexec tool to install the Connector/NET package automatically (using the default options) with no notification to the user. Using this option you cannot select options and no prompts, messages or dialog boxes will be displayed.

C:\> msiexec /package conector-net.msi /quiet

To provide a progress bar to the user during automatic installation, but still without presenting the user with a dialog box of the ability to select options, use the /passive option.

27.2.2.1.2. Installing Connector/NET using the Zip package

If you are having problems running the installer, you can download a .zip file without an installer as an alternative. That file is called mysql-connector-net-version-noinstall.zip. Once downloaded, you can extract the files to a location of your choice.

The .zip file contains the following directories:

  • bin - Connector/NET MySQL libraries for different versions of the .NET environment.

  • doc - contains a CHM of the Connector/NET documentation.

  • Samples - sample code and applications that use the Connector/NET component.

  • mysqlclient - the source code for the Connector/NET component.

  • testsuite - the test suite used to verify the operation of the Connector/NET component.

27.2.2.2. Installing Connector/NET on Unix with Mono

There is no installer available for installing the Connector/NET component on your Unix installation. However, the installation is very simple. Before installing, please ensure that you have a working Mono project installation.

Note that you should only install the Connector/NET component on Unix environments where you want to connect to a MySQL server through the Mono project. If you are deploying or developing on a different environment such as Java or Perl then you should use a more appropriate connectivity component. See Chapter 27, Connectors, or Chapter 26, APIs and Libraries, for more information.

To install Connector/NET on Unix/Mono:

  1. Download the mysql-connector-net-version-noinstall.zip and extract the contents.

  2. Copy the MySql.Data.dll file to your Mono project installation folder.

  3. You must register the Connector/NET component in the Global Assembly Cache using the gacutil command:

    shell> gacutil /i MySql.Data.dll

Once installed, applications that are compiled with the Connector/NET component need no further changes. However, you must ensure that when you compile your applications you include the Connector/NET component using the -r:MySqlData.dll command-line option.

27.2.2.3. Installing Connector/NET using the Source

Caution

You should read this section only if you are interested in helping us test our new code. If you just want to get Connector/NET up and running on your system, you should use a standard release distribution.

To be able to access the Connector/NET source tree, you must have Subversion installed. Subversion is freely available from http://subversion.tigris.org/.

The most recent development source tree is available from our public Subversion trees at http://dev.mysql.com/tech-resources/sources.html.

To checkout out the Connector/NET sources, change to the directory where you want the copy of the Connector/NET tree to be stored, then use the following command:

shell> svn co
http://svn.mysql.com/svnpublic/connector-net

A Visual Studio project is included in the source which you can use to build Connector/NET.

27.2.3. Connector/NET Examples and Usage Guide

Connector/NET comprises several classes that are used to connect to the database, execute queries and statements, and manage query results.

The following are the major classes of Connector/NET:

  • MySqlCommand: Represents an SQL statement to execute against a MySQL database.

  • MySqlCommandBuilder: Automatically generates single-table commands used to reconcile changes made to a DataSet with the associated MySQL database.

  • MySqlConnection: Represents an open connection to a MySQL Server database.

  • MySqlDataAdapter: Represents a set of data commands and a database connection that are used to fill a data set and update a MySQL database.

  • MySqlDataReader: Provides a means of reading a forward-only stream of rows from a MySQL database.

  • MySqlException: The exception that is thrown when MySQL returns an error.

  • MySqlHelper: Helper class that makes it easier to work with the provider.

  • MySqlTransaction: Represents an SQL transaction to be made in a MySQL database.

This section contains basic information and examples for each of the above classes. For a more detailed reference guide please see Section 27.2.4, “Connector/NET Reference”.

27.2.3.1. Using MySqlCommand

Represents a SQL statement to execute against a MySQL database. This class cannot be inherited.

MySqlCommand features the following methods for executing commands at a MySQL database:

Item Description
ExecuteReader Executes commands that return rows.
ExecuteNonQuery Executes commands such as SQL INSERT, DELETE, and UPDATE statements.
ExecuteScalar Retrieves a single value (for example, an aggregate value) from a database.

You can reset the CommandText property and reuse the MySqlCommand object. However, you must close the MySqlDataReader before you can execute a new or previous command.

If a MySqlException is generated by the method executing a MySqlCommand, the MySqlConnection remains open. It is the responsibility of the programmer to close the connection.

Note

Using the '@' symbol for parameters is now the preferred approach although the old pattern of using '?' is still supported.

Please be aware however that using '@' can cause conflicts when user variables are also used. To help with this situation please see the documentation on the Allow User Variables connection string option, which can be found here: Section 27.2.3.3.3, “ConnectionString”. The Old Syntax connection string option has now been deprecated.

Examples

The following example creates a MySqlCommand and a MySqlConnection. The MySqlConnection is opened and set as the Connection for the MySqlCommand. The example then calls ExecuteNonQuery, and closes the connection. To accomplish this, the ExecuteNonQuery is passed a connection string and a query string that is a SQL INSERT statement.

Visual Basic example:

  Public Sub InsertRow(myConnectionString As String)
  " If the connection string is null, use a default.
  If myConnectionString = "" Then
    myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass"
  End If
  Dim myConnection As New MySqlConnection(myConnectionString)
  Dim myInsertQuery As String = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)"
  Dim myCommand As New MySqlCommand(myInsertQuery)
  myCommand.Connection = myConnection
  myConnection.Open()
  myCommand.ExecuteNonQuery()
  myCommand.Connection.Close()
End Sub
    

C# example:

  public void InsertRow(string myConnectionString) 
{
  // If the connection string is null, use a default.
  if(myConnectionString == "") 
  {
    myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass";
  }
  MySqlConnection myConnection = new MySqlConnection(myConnectionString);
  string myInsertQuery = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)";
  MySqlCommand myCommand = new MySqlCommand(myInsertQuery);
  myCommand.Connection = myConnection;
  myConnection.Open();
  myCommand.ExecuteNonQuery();
  myCommand.Connection.Close();
}
    
27.2.3.1.1. Class MySqlCommand Constructor Form 1

Overload methods for MySqlCommand

Initializes a new instance of the MySqlCommand class.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Note

This example shows how to use one of the overloaded versions of the MySqlCommand constructor. For other examples that might be available, see the individual overload topics.

Visual Basic example:

  Public Sub CreateMySqlCommand()
    Dim myConnection As New MySqlConnection _
        ("Persist Security Info=False;database=test;server=myServer")
    myConnection.Open()
    Dim myTrans As MySqlTransaction = myConnection.BeginTransaction()
    Dim mySelectQuery As String = "SELECT * FROM MyTable"
    Dim myCommand As New MySqlCommand(mySelectQuery, myConnection, myTrans)
    myCommand.CommandTimeout = 20
  End Sub
  

C# example:

  public void CreateMySqlCommand() 
  {
    MySqlConnection myConnection = new MySqlConnection("Persist Security Info=False;
      database=test;server=myServer");
    myConnection.Open();
    MySqlTransaction myTrans = myConnection.BeginTransaction();
    string mySelectQuery = "SELECT * FROM myTable";
    MySqlCommand myCommand = new MySqlCommand(mySelectQuery, myConnection,myTrans);
    myCommand.CommandTimeout = 20;
  }
  

C++ example:

  public:
  void CreateMySqlCommand()
  {
    MySqlConnection* myConnection = new MySqlConnection(S"Persist Security Info=False;
      database=test;server=myServer");
    myConnection->Open();
    MySqlTransaction* myTrans = myConnection->BeginTransaction();
    String* mySelectQuery = S"SELECT * FROM myTable";
    MySqlCommand* myCommand = new MySqlCommand(mySelectQuery, myConnection, myTrans);
    myCommand->CommandTimeout = 20;
  };
  

Initializes a new instance of the MySqlCommand class.

The base constructor initializes all fields to their default values. The following table shows initial property values for an instance of MySqlCommand.

Properties Initial Value
CommandText empty string ("")
CommandTimeout 0
CommandType CommandType.Text
Connection Null

You can change the value for any of these properties through a separate call to the property.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Visual Basic example:

Public Sub CreateMySqlCommand()
    Dim myCommand As New MySqlCommand()
    myCommand.CommandType = CommandType.Text
End Sub

C# example:

public void CreateMySqlCommand() 
{
   MySqlCommand myCommand = new MySqlCommand();
   myCommand.CommandType = CommandType.Text;
}
27.2.3.1.2. Class MySqlCommand Constructor Form 2

Initializes a new instance of the MySqlCommand class with the text of the query.

Parameters: The text of the query.

When an instance of MySqlCommand is created, the following read/write properties are set to initial values.

Properties Initial Value
CommandText cmdText
CommandTimeout 0
CommandType CommandType.Text
Connection Null

You can change the value for any of these properties through a separate call to the property.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Visual Basic example:

Public Sub CreateMySqlCommand()
  Dim sql as String = "SELECT * FROM mytable"
    Dim myCommand As New MySqlCommand(sql)
    myCommand.CommandType = CommandType.Text
End Sub

C# example:

public void CreateMySqlCommand() 
{
  string sql = "SELECT * FROM mytable";
  MySqlCommand myCommand = new MySqlCommand(sql);
  myCommand.CommandType = CommandType.Text;
}
27.2.3.1.3. Class MySqlCommand Constructor Form 3

Initializes a new instance of the MySqlCommand class with the text of the query and a MySqlConnection.

Parameters: The text of the query.

Parameters: A MySqlConnection that represents the connection to an instance of SQL Server.

When an instance of MySqlCommand is created, the following read/write properties are set to initial values.

Properties Initial Value
CommandText cmdText
CommandTimeout 0
CommandType CommandType.Text
Connection connection

You can change the value for any of these properties through a separate call to the property.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Visual Basic example:

Public Sub CreateMySqlCommand()
  Dim conn as new MySqlConnection("server=myServer")
  Dim sql as String = "SELECT * FROM mytable"
    Dim myCommand As New MySqlCommand(sql, conn)
    myCommand.CommandType = CommandType.Text
End Sub

C# example:

public void CreateMySqlCommand() 
{
  MySqlConnection conn = new MySqlConnection("server=myserver")
  string sql = "SELECT * FROM mytable";
  MySqlCommand myCommand = new MySqlCommand(sql, conn);
  myCommand.CommandType = CommandType.Text;
}
27.2.3.1.4. Class MySqlCommand Constructor Form 4

Initializes a new instance of the MySqlCommand class with the text of the query, a MySqlConnection, and the MySqlTransaction.

Parameters: The text of the query.

Parameters: A MySqlConnection that represents the connection to an instance of SQL Server.

Parameters: The MySqlTransaction in which the MySqlCommand executes.

When an instance of MySqlCommand is created, the following read/write properties are set to initial values.

Properties Initial Value
CommandText cmdText
CommandTimeout 0
CommandType CommandType.Text
Connection connection

You can change the value for any of these properties through a separate call to the property.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Visual Basic example:

Public Sub CreateMySqlCommand()
  Dim conn as new MySqlConnection("server=myServer")
  conn.Open();
  Dim txn as MySqlTransaction = conn.BeginTransaction()
  Dim sql as String = "SELECT * FROM mytable"
    Dim myCommand As New MySqlCommand(sql, conn, txn)
    myCommand.CommandType = CommandType.Text
End Sub

C# example:

public void CreateMySqlCommand() 
{
  MySqlConnection conn = new MySqlConnection("server=myserver")
  conn.Open();
  MySqlTransaction txn = conn.BeginTransaction();
  string sql = "SELECT * FROM mytable";
  MySqlCommand myCommand = new MySqlCommand(sql, conn, txn);
  myCommand.CommandType = CommandType.Text;
}
27.2.3.1.5. ExecuteNonQuery

Executes a SQL statement against the connection and returns the number of rows affected.

Returns: Number of rows affected

You can use ExecuteNonQuery to perform any type of database operation, however any resultsets returned will not be available. Any output parameters used in calling a stored procedure will be populated with data and can be retrieved after execution is complete. For UPDATE, INSERT, and DELETE statements, the return value is the number of rows affected by the command. For all other types of statements, the return value is -1.

Examples

The following example creates a MySqlCommand and then executes it using ExecuteNonQuery. The example is passed a string that is a SQL statement (such as UPDATE, INSERT, or DELETE) and a string to use to connect to the data source.

Visual Basic example:

    Public Sub CreateMySqlCommand(myExecuteQuery As String, myConnection As MySqlConnection)
      Dim myCommand As New MySqlCommand(myExecuteQuery, myConnection)
      myCommand.Connection.Open()
      myCommand.ExecuteNonQuery()
      myConnection.Close()
    End Sub 
  

C# example:

    public void CreateMySqlCommand(string myExecuteQuery, MySqlConnection myConnection) 
    {
      MySqlCommand myCommand = new MySqlCommand(myExecuteQuery, myConnection);
      myCommand.Connection.Open();
      myCommand.ExecuteNonQuery();
      myConnection.Close();
    }
  
27.2.3.1.6. ExecuteReader1

Sends the CommandText to the MySqlConnectionConnection, and builds a MySqlDataReader using one of the CommandBehavior values.

Parameters: One of the CommandBehavior values.

When the CommandType property is set to StoredProcedure, the CommandText property should be set to the name of the stored procedure. The command executes this stored procedure when you call ExecuteReader.

The MySqlDataReader supports a special mode that enables large binary values to be read efficiently. For more information, see the SequentialAccess setting for CommandBehavior.

While the MySqlDataReader is in use, the associated MySqlConnection is busy serving the MySqlDataReader. While in this state, no other operations can be performed on the MySqlConnection other than closing it. This is the case until the MySqlDataReader.Close method of the MySqlDataReader is called. If the MySqlDataReader is created with CommandBehavior set to CloseConnection, closing the MySqlDataReader closes the connection automatically.

Note

When calling ExecuteReader with the SingleRow behavior, you should be aware that using a limit clause in your SQL will cause all rows (up to the limit given) to be retrieved by the client. The MySqlDataReader.Read method will still return false after the first row but pulling all rows of data into the client will have a performance impact. If the limit clause is not necessary, it should be avoided.

Returns: A MySqlDataReader object.

27.2.3.1.7. Using ExecuteReader

Sends the CommandText to the MySqlConnectionConnection and builds a MySqlDataReader.

Returns: A MySqlDataReader object.

When the CommandType property is set to StoredProcedure, the CommandText property should be set to the name of the stored procedure. The command executes this stored procedure when you call ExecuteReader.

While the MySqlDataReader is in use, the associated MySqlConnection is busy serving the MySqlDataReader. While in this state, no other operations can be performed on the MySqlConnection other than closing it. This is the case until the MySqlDataReader.Close method of the MySqlDataReader is called.

Examples

The following example creates a MySqlCommand, then executes it by passing a string that is a SQL SELECT statement, and a string to use to connect to the data source.

Visual Basic example:

Public Sub CreateMySqlDataReader(mySelectQuery As String, myConnection As MySqlConnection)
    Dim myCommand As New MySqlCommand(mySelectQuery, myConnection)
    myConnection.Open()
    Dim myReader As MySqlDataReader
    myReader = myCommand.ExecuteReader()
    Try
    While myReader.Read()
        Console.WriteLine(myReader.GetString(0))
    End While
Finally
    myReader.Close
    myConnection.Close
    End Try
End Sub

C# example:

public void CreateMySqlDataReader(string mySelectQuery, MySqlConnection myConnection) 
 {
    MySqlCommand myCommand = new MySqlCommand(mySelectQuery, myConnection);
    myConnection.Open();
    MySqlDataReader myReader;
    myReader = myCommand.ExecuteReader();
    try
    {
      while(myReader.Read()) 
      {
        Console.WriteLine(myReader.GetString(0));
      }
    }
    finally
    {
      myReader.Close();
      myConnection.Close();
    }
 }  
 
27.2.3.1.8. Using Prepare

Creates a prepared version of the command on an instance of MySQL Server.

Prepared statements are only supported on MySQL version 4.1 and higher. Calling prepare while connected to earlier versions of MySQL will succeed but will execute the statement in the same way as unprepared.

Examples

The following example demonstrates the use of the Prepare method.

Visual Basic example:

  public sub PrepareExample()
    Dim cmd as New MySqlCommand("INSERT INTO mytable VALUES (?val)", myConnection)
    cmd.Parameters.Add( "?val", 10 )
    cmd.Prepare()
    cmd.ExecuteNonQuery()
    
    cmd.Parameters(0).Value = 20
    cmd.ExecuteNonQuery()
  end sub
  

C# example:

  private void PrepareExample()
  {
    MySqlCommand cmd = new MySqlCommand("INSERT INTO mytable VALUES (@val)", myConnection);
    cmd.Parameters.Add( "@val", 10 );
    cmd.Prepare();
    cmd.ExecuteNonQuery();
    
    cmd.Parameters[0].Value = 20;
    cmd.ExecuteNonQuery();
  }
  
27.2.3.1.9. ExecuteScalar

Executes the query, and returns the first column of the first row in the result set returned by the query. Extra columns or rows are ignored.

Returns: The first column of the first row in the result set, or a null reference if the result set is empty

Use the ExecuteScalar method to retrieve a single value (for example, an aggregate value) from a database. This requires less code than using the ExecuteReader method, and then performing the operations necessary to generate the single value using the data returned by a MySqlDataReader

A typical ExecuteScalar query can be formatted as in the following C# example:

C# example:

cmd.CommandText = "select count(*) from region";
Int32 count = (int32) cmd.ExecuteScalar();

Examples

The following example creates a MySqlCommand and then executes it using ExecuteScalar. The example is passed a string that is a SQL statement that returns an aggregate result, and a string to use to connect to the data source.

Visual Basic example:

Public Sub CreateMySqlCommand(myScalarQuery As String, myConnection As MySqlConnection)
    Dim myCommand As New MySqlCommand(myScalarQuery, myConnection)
    myCommand.Connection.Open()
    myCommand.ExecuteScalar()
    myConnection.Close()
End Sub 

C# example:

public void CreateMySqlCommand(string myScalarQuery, MySqlConnection myConnection) 
 {
    MySqlCommand myCommand = new MySqlCommand(myScalarQuery, myConnection);
    myCommand.Connection.Open();
    myCommand.ExecuteScalar();
    myConnection.Close();
 }

C++ example:

public:
    void CreateMySqlCommand(String* myScalarQuery, MySqlConnection* myConnection)
    {
        MySqlCommand* myCommand = new MySqlCommand(myScalarQuery, myConnection);
        myCommand->Connection->Open();
        myCommand->ExecuteScalar();
        myConnection->Close();
    }  
27.2.3.1.10. CommandText

Gets or sets the SQL statement to execute at the data source.

Value: The SQL statement or stored procedure to execute. The default is an empty string.

When the CommandType property is set to StoredProcedure, the CommandText property should be set to the name of the stored procedure. The user may be required to use escape character syntax if the stored procedure name contains any special characters. The command executes this stored procedure when you call one of the Execute methods.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Visual Basic example:

Public Sub CreateMySqlCommand()
    Dim myCommand As New MySqlCommand()
    myCommand.CommandText = "SELECT * FROM Mytable ORDER BY id"
    myCommand.CommandType = CommandType.Text
End Sub

C# example:

public void CreateMySqlCommand() 
 {
    MySqlCommand myCommand = new MySqlCommand();
    myCommand.CommandText = "SELECT * FROM mytable ORDER BY id";
    myCommand.CommandType = CommandType.Text;
 }  
27.2.3.1.11. CommandTimeout

Gets or sets the wait time before terminating the attempt to execute a command and generating an error.

Value: The time (in seconds) to wait for the command to execute. The default is 0 seconds.

MySQL currently does not support any method of canceling a pending or executing operation. All commands issued against a MySQL server will execute until completion or until an exception occurs.

MySQL Enterprise MySQL Enterprise subscribers will find more information about CommandTimeout in the Knowledge Base article, Why CommandTimeout is not Supported. Access to the MySQL Knowledge Base collection of articles is one of the advantages of subscribing to MySQL Enterprise. For more information see http://www.mysql.com/products/enterprise/advisors.html.

27.2.3.1.12. CommandType

Gets or sets a value indicating how the CommandText property is to be interpreted.

Value: One of the System.Data.CommandType values. The default is Text.

When you set the CommandType property to StoredProcedure, you should set the CommandText property to the name of the stored procedure. The command executes this stored procedure when you call one of the Execute methods.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Visual Basic example:

Public Sub CreateMySqlCommand()
    Dim myCommand As New MySqlCommand()
    myCommand.CommandType = CommandType.Text
End Sub

C# example:

public void CreateMySqlCommand() 
{
   MySqlCommand myCommand = new MySqlCommand();
   myCommand.CommandType = CommandType.Text;
}
27.2.3.1.13. Connection

Gets or sets the MySqlConnection used by this instance of the MySqlCommand.

Value: The connection to a data source. The default value is a null reference (Nothing in Visual Basic).

If you set Connection while a transaction is in progress and the Transaction property is not null, an InvalidOperationException is generated. If the Transaction property is not null and the transaction has already been committed or rolled back, Transaction is set to null.

Examples

The following example creates a MySqlCommand and sets some of its properties.

Visual Basic example:

Public Sub CreateMySqlCommand()
    Dim mySelectQuery As String = "SELECT * FROM mytable ORDER BY id"
    Dim myConnectString As String = "Persist Security Info=False;database=test;server=myServer"
    Dim myCommand As New MySqlCommand(mySelectQuery)
    myCommand.Connection = New MySqlConnection(myConnectString)
    myCommand.CommandType = CommandType.Text
End Sub

C# example:

public void CreateMySqlCommand() 
 {
    string mySelectQuery = "SELECT * FROM mytable ORDER BY id";
    string myConnectString = "Persist Security Info=False;database=test;server=myServer";
    MySqlCommand myCommand = new MySqlCommand(mySelectQuery);
    myCommand.Connection = new MySqlConnection(myConnectString);
    myCommand.CommandType = CommandType.Text;
 }  
 
27.2.3.1.14. IsPrepared

Returns true if the statement is prepared.

27.2.3.1.15. Parameters

Get the MySqlParameterCollection

Value: The parameters of the SQL statement or stored procedure. The default is an empty collection.

Connector/Net does not support unnamed parameters. Every parameter added to the collection must have an associated name.

Examples

The following example creates a MySqlCommand and displays its parameters. To accomplish this, the method is passed a MySqlConnection, a query string that is a SQL SELECT statement, and an array of MySqlParameter objects.

Visual Basic example:

Public Sub CreateMySqlCommand(myConnection As MySqlConnection, _
mySelectQuery As String, myParamArray() As MySqlParameter)
    Dim myCommand As New MySqlCommand(mySelectQuery, myConnection)
    myCommand.CommandText = "SELECT id, name FROM mytable WHERE age=@age"
    myCommand.UpdatedRowSource = UpdateRowSource.Both
    myCommand.Parameters.Add(myParamArray)
    Dim j As Integer
    For j = 0 To myCommand.Parameters.Count - 1
       myCommand.Parameters.Add(myParamArray(j))
    Next j
    Dim myMessage As String = ""
    Dim i As Integer
    For i = 0 To myCommand.Parameters.Count - 1
        myMessage += myCommand.Parameters(i).ToString() & ControlChars.Cr
    Next i
    Console.WriteLine(myMessage)
End Sub

C# example:

public void CreateMySqlCommand(MySqlConnection myConnection, string mySelectQuery, 
  MySqlParameter[] myParamArray) 
{
   MySqlCommand myCommand = new MySqlCommand(mySelectQuery, myConnection);
   myCommand.CommandText = "SELECT id, name FROM mytable WHERE age=@age";    
   myCommand.Parameters.Add(myParamArray);
   for (int j=0; j<myParamArray.Length; j++)
   {
      myCommand.Parameters.Add(myParamArray[j]) ;
   }
   string myMessage = "";
   for (int i = 0; i < myCommand.Parameters.Count; i++) 
   {
      myMessage += myCommand.Parameters[i].ToString() + "\n";
   }
   MessageBox.Show(myMessage);
}  
27.2.3.1.16. Transaction

Gets or sets the MySqlTransaction within which the MySqlCommand executes.

Value: The MySqlTransaction. The default value is a null reference (Nothing in Visual Basic).

You cannot set the Transaction property if it is already set to a specific value, and the command is in the process of executing. If you set the transaction property to a MySqlTransaction object that is not connected to the same MySqlConnection as the MySqlCommand object, an exception will be thrown the next time you attempt to execute a statement.

27.2.3.1.17. UpdatedRowSource

Gets or sets how command results are applied to the DataRow when used by the System.Data.Common.DbDataAdapter.Update method of the System.Data.Common.DbDataAdapter.

Value: One of the UpdateRowSource values.

The default System.Data.UpdateRowSource value is Both unless the command is automatically generated (as in the case of the MySqlCommandBuilder), in which case the default is None.

27.2.3.2. Using MySqlCommandBuilder

Automatically generates single-table commands used to reconcile changes made to a DataSet with the associated MySQL database. This class cannot be inherited.

The MySqlDataAdapter does not automatically generate the SQL statements required to reconcile changes made to a System.Data.DataSetDataSet with the associated instance of MySQL. However, you can create a MySqlCommandBuilder object to automatically generate SQL statements for single-table updates if you set the MySqlDataAdapter.SelectCommandSelectCommand property of the MySqlDataAdapter. Then, any additional SQL statements that you do not set are generated by the MySqlCommandBuilder.

The MySqlCommandBuilder registers itself as a listener for MySqlDataAdapter.OnRowUpdatingRowUpdating events whenever you set the DataAdapter property. You can only associate one MySqlDataAdapter or MySqlCommandBuilder object with each other at one time.

To generate INSERT, UPDATE, or DELETE statements, the MySqlCommandBuilder uses the SelectCommand property to retrieve a required set of metadata automatically. If you change the SelectCommand after the metadata has is retrieved (for example, after the first update), you should call the RefreshSchema method to update the metadata.

The SelectCommand must also return at least one primary key or unique column. If none are present, an InvalidOperation exception is generated, and the commands are not generated.

When using MySqlCommandbuilder and INSERT you should set the ReturnGeneratedIdentifiers property to true to ensure that AUTO_INCREMENT fields in MySQL tables return the automatically generated value.

The MySqlCommandBuilder also uses the MySqlCommand.ConnectionConnection, MySqlCommand.CommandTimeoutCommandTimeout, and MySqlCommand.TransactionTransaction properties referenced by the SelectCommand. The user should call RefreshSchema if any of these properties are modified, or if the SelectCommand itself is replaced. Otherwise the MySqlDataAdapter.InsertCommandInsertCommand, MySqlDataAdapter.UpdateCommandUpdateCommand, and MySqlDataAdapter.DeleteCommandDeleteCommand properties retain their previous values.

If you call Dispose, the MySqlCommandBuilder is disassociated from the MySqlDataAdapter, and the generated commands are no longer used.

Note

Caution must be used when using MySqlCommandBuilder on MySql 4.0 systems. With MySQL 4.0, database/schema information is not provided to the connector for a query. This means that a query that pulls columns from two identically named tables in two or more different databases will not cause an exception to be thrown but will not work correctly. Even more dangerous is the situation where your select statement references database X but is executed in database Y and both databases have tables with similar layouts. This situation can cause unwanted changes or deletes. This note does not apply to MySQL versions 4.1 and later.

Examples

The following example uses the MySqlCommand, along MySqlDataAdapter and MySqlConnection, to select rows from a data source. The example is passed an initialized System.Data.DataSet, a connection string, a query string that is a SQL SELECT statement, and a string that is the name of the database table. The example then creates a MySqlCommandBuilder.

Visual Basic example:

  Public Shared Function SelectRows(myConnection As String, mySelectQuery As String, myTableName As String) As DataSet
    Dim myConn As New MySqlConnection(myConnection)
    Dim myDataAdapter As New MySqlDataAdapter()
    myDataAdapter.SelectCommand = New MySqlCommand(mySelectQuery, myConn)
    Dim cb As SqlCommandBuilder = New MySqlCommandBuilder(myDataAdapter)
    myConn.Open()
    Dim ds As DataSet = New DataSet
    myDataAdapter.Fill(ds, myTableName)
    ' Code to modify data in DataSet here 
    ' Without the MySqlCommandBuilder this line would fail.
    myDataAdapter.Update(ds, myTableName)
    myConn.Close()
  End Function 'SelectRows
    

C# example:

  public static DataSet SelectRows(string myConnection, string mySelectQuery, string myTableName)
  {
  MySqlConnection myConn = new MySqlConnection(myConnection);
  MySqlDataAdapter myDataAdapter = new MySqlDataAdapter();
  myDataAdapter.SelectCommand = new MySqlCommand(mySelectQuery, myConn);
  MySqlCommandBuilder cb = new MySqlCommandBuilder(myDataAdapter);
  myConn.Open();
  DataSet ds = new DataSet();
  myDataAdapter.Fill(ds, myTableName);
  //code to modify data in DataSet here
  //Without the MySqlCommandBuilder this line would fail
  myDataAdapter.Update(ds, myTableName);
  myConn.Close();
  return ds;
  }
    
27.2.3.2.1. Class MySqlCommandBuilder Constructor

Initializes a new instance of the MySqlCommandBuilder class.

27.2.3.2.2. Class MySqlCommandBuilder Constructor Form 1

Initializes a new instance of the MySqlCommandBuilder class and sets the last one wins property.

Parameters: False to generate change protection code. True otherwise.

The lastOneWins parameter indicates whether SQL code should be included with the generated DELETE and UPDATE commands that checks the underlying data for changes. If lastOneWins is true then this code is not included and data records could be overwritten in a multi-user or multi-threaded environments. Setting lastOneWins to false will include this check which will cause a concurrency exception to be thrown if the underlying data record has changed without our knowledge.

27.2.3.2.3. Class MySqlCommandBuilder Constructor Form 2

Initializes a new instance of the MySqlCommandBuilder class with the associated MySqlDataAdapter object.

Parameters: The MySqlDataAdapter to use.

The MySqlCommandBuilder registers itself as a listener for MySqlDataAdapter.RowUpdating events that are generated by the MySqlDataAdapter specified in this property.

When you create a new instance MySqlCommandBuilder, any existing MySqlCommandBuilder associated with this MySqlDataAdapter is released.

27.2.3.2.4. Class MySqlCommandBuilder Constructor Form 3

Initializes a new instance of the MySqlCommandBuilder class with the associated MySqlDataAdapter object.

Parameters: The MySqlDataAdapter to use.

Parameters: False to generate change protection code. True otherwise.

The MySqlCommandBuilder registers itself as a listener for MySqlDataAdapter.RowUpdating events that are generated by the MySqlDataAdapter specified in this property.

When you create a new instance MySqlCommandBuilder, any existing MySqlCommandBuilder associated with this MySqlDataAdapter is released.

The lastOneWins parameter indicates whether SQL code should be included with the generated DELETE and UPDATE commands that checks the underlying data for changes. If lastOneWins is true then this code is not included and data records could be overwritten in a multi-user or multi-threaded environments. Setting lastOneWins to false will include this check which will cause a concurrency exception to be thrown if the underlying data record has changed without our knowledge.

27.2.3.2.5. DataAdapter

Gets or sets a MySqlDataAdapter object for which SQL statements are automatically generated.

Value: A MySqlDataAdapter object.

The MySqlCommandBuilder registers itself as a listener for MySqlDataAdapter.RowUpdating events that are generated by the MySqlDataAdapter specified in this property.

When you create a new instance MySqlCommandBuilder, any existing MySqlCommandBuilder associated with this MySqlDataAdapter is released.

27.2.3.2.6. QuotePrefix

Gets or sets the beginning character or characters to use when specifying MySQL database objects (for example, tables or columns) whose names contain characters such as spaces or reserved tokens.

Value: The beginning character or characters to use. The default value is `.

Database objects in MySQL can contain special characters such as spaces that would make normal SQL strings impossible to correctly parse. Use of the QuotePrefix and the QuoteSuffix properties allows the MySqlCommandBuilder to build SQL statements that handle this situation.

27.2.3.2.7. QuoteSuffix

Gets or sets the beginning character or characters to use when specifying MySQL database objects (for example, tables or columns) whose names contain characters such as spaces or reserved tokens.

Value: The beginning character or characters to use. The default value is `.

Database objects in MySQL can contain special characters such as spaces that would make normal SQL strings impossible to correctly parse. Use of the QuotePrefix and the QuoteSuffix properties allows the MySqlCommandBuilder to build SQL statements that handle this situation.

27.2.3.2.8. DeriveParameters

27.2.3.2.9. GetDeleteCommand

Gets the automatically generated MySqlCommand object required to perform deletions on the database.

Returns: The MySqlCommand object generated to handle delete operations.

An application can use the GetDeleteCommand method for informational or troubleshooting purposes because it returns the MySqlCommand object to be executed.

You can also use GetDeleteCommand as the basis of a modified command. For example, you might call GetDeleteCommand and modify the MySqlCommand.CommandTimeout value, and then explicitly set that on the MySqlDataAdapter.

After the SQL statement is first generated, the application must explicitly call RefreshSchema if it changes the statement in any way. Otherwise, the GetDeleteCommand will be still be using information from the previous statement, which might not be correct. The SQL statements are first generated either when the application calls System.Data.Common.DataAdapter.Update or GetDeleteCommand.

27.2.3.2.10. GetInsertCommand

Gets the automatically generated MySqlCommand object required to perform insertions on the database.

Returns: The MySqlCommand object generated to handle insert operations.

An application can use the GetInsertCommand method for informational or troubleshooting purposes because it returns the MySqlCommand object to be executed.

You can also use the GetInsertCommand as the basis of a modified command. For example, you might call GetInsertCommand and modify the MySqlCommand.CommandTimeout value, and then explicitly set that on the MySqlDataAdapter.

After the SQL statement is first generated, the application must explicitly call RefreshSchema if it changes the statement in any way. Otherwise, the GetInsertCommand will be still be using information from the previous statement, which might not be correct. The SQL statements are first generated either when the application calls System.Data.Common.DataAdapter.Update or GetInsertCommand.

27.2.3.2.11. GetUpdateCommand

Gets the automatically generated MySqlCommand object required to perform updates on the database.

Returns: The MySqlCommand object generated to handle update operations.

An application can use the GetUpdateCommand method for informational or troubleshooting purposes because it returns the MySqlCommand object to be executed.

You can also use GetUpdateCommand as the basis of a modified command. For example, you might call GetUpdateCommand and modify the MySqlCommand.CommandTimeout value, and then explicitly set that on the MySqlDataAdapter.

After the SQL statement is first generated, the application must explicitly call RefreshSchema if it changes the statement in any way. Otherwise, the GetUpdateCommand will be still be using information from the previous statement, which might not be correct. The SQL statements are first generated either when the application calls System.Data.Common.DataAdapter.Update or GetUpdateCommand.

27.2.3.2.12. RefreshSchema

Refreshes the database schema information used to generate INSERT, UPDATE, or DELETE statements.

An application should call RefreshSchema whenever the SELECT statement associated with the MySqlCommandBuilder changes.

An application should call RefreshSchema whenever the MySqlDataAdapter.SelectCommand value of the MySqlDataAdapter changes.

MySQL Enterprise MySQL Enterprise subscribers will find more information on this topic in the Knowledge Base article, Understanding MySqlCommandBuilder and the LastOneWins Setting . For information about subscribing to MySQL Enterprise see http://www.mysql.com/products/enterprise/advisors.html.

27.2.3.3. Using MySqlConnection

Represents an open connection to a MySQL Server database. This class cannot be inherited.

A MySqlConnection object represents a session to a MySQL Server data source. When you create an instance of MySqlConnection, all properties are set to their initial values. For a list of these values, see the MySqlConnection constructor.

If the MySqlConnection goes out of scope, it is not closed. Therefore, you must explicitly close the connection by calling MySqlConnection.Close or MySqlConnection.Dispose.

Examples

The following example creates a MySqlCommand and a MySqlConnection. The MySqlConnection is opened and set as the MySqlCommand.Connection for the MySqlCommand. The example then calls MySqlCommand.ExecuteNonQuery, and closes the connection. To accomplish this, the ExecuteNonQuery is passed a connection string and a query string that is a SQL INSERT statement.

Visual Basic example:

  Public Sub InsertRow(myConnectionString As String)
    ' If the connection string is null, use a default.
    If myConnectionString = "" Then
      myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass"
    End If
    Dim myConnection As New MySqlConnection(myConnectionString)
    Dim myInsertQuery As String = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)"
    Dim myCommand As New MySqlCommand(myInsertQuery)
    myCommand.Connection = myConnection
    myConnection.Open()
    myCommand.ExecuteNonQuery()
    myCommand.Connection.Close()
  End Sub
  

C# example:

  public void InsertRow(string myConnectionString) 
  {
    // If the connection string is null, use a default.
    if(myConnectionString == "") 
    {
      myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass";
    }
    MySqlConnection myConnection = new MySqlConnection(myConnectionString);
    string myInsertQuery = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)";
    MySqlCommand myCommand = new MySqlCommand(myInsertQuery);
    myCommand.Connection = myConnection;
    myConnection.Open();
    myCommand.ExecuteNonQuery();
    myCommand.Connection.Close();
  }
  
27.2.3.3.1. Class MySqlConnection Constructor (Default)

Initializes a new instance of the MySqlConnection class.

When a new instance of MySqlConnection is created, the read/write properties are set to the following initial values unless they are specifically set using their associated keywords in the ConnectionString property.

Properties Initial Value
ConnectionString empty string ("")
ConnectionTimeout 15
Database empty string ("")
DataSource empty string ("")
ServerVersion empty string ("")

You can change the value for these properties only by using the ConnectionString property.

Examples

Overload methods for MySqlConnection

Initializes a new instance of the MySqlConnection class.

27.2.3.3.2. Class MySqlConnection Constructor Form 1

Initializes a new instance of the MySqlConnection class when given a string containing the connection string.

When a new instance of MySqlConnection is created, the read/write properties are set to the following initial values unless they are specifically set using their associated keywords in the ConnectionString property.

Properties Initial Value
ConnectionString empty string ("")
ConnectionTimeout 15
Database empty string ("")
DataSource empty string ("")
ServerVersion empty string ("")

You can change the value for these properties only by using the ConnectionString property.

Examples

Parameters: The connection properties used to open the MySQL database.

27.2.3.3.3. ConnectionString

Gets or sets the string used to connect to a MySQL Server database.

The ConnectionString returned may not be exactly like what was originally set but will be indentical in terms of keyword/value pairs. Security information will not be included unless the Persist Security Info value is set to true.

You can use the ConnectionString property to connect to a database. The following example illustrates a typical connection string.

"Persist Security Info=False;database=MyDB;»
    server=MySqlServer;user id=myUser;Password=myPass"

The ConnectionString property can be set only when the connection is closed. Many of the connection string values have corresponding read-only properties. When the connection string is set, all of these properties are updated, except when an error is detected. In this case, none of the properties are updated. MySqlConnection properties return only those settings contained in the ConnectionString.

To connect to a local machine, specify "localhost" for the server. If you do not specify a server, localhost is assumed.

Resetting the ConnectionString on a closed connection resets all connection string values (and related properties) including the password. For example, if you set a connection string that includes "Database= MyDb", and then reset the connection string to "Data Source=myserver;User Id=myUser;Password=myPass", the MySqlConnection.Database property is no longer set to MyDb.

The connection string is parsed immediately after being set. If errors in syntax are found when parsing, a runtime exception, such as ArgumentException, is generated. Other errors can be found only when an attempt is made to open the connection.

The basic format of a connection string consists of a series of keyword/value pairs separated by semicolons. The equal sign (=) connects each keyword and its value. Additional notes on setting values for options:

  • To include values that contain a semicolon, single-quote character, or double-quote character, the value must be enclosed in double quotes. If the value contains both a semicolon and a double-quote character, the value can be enclosed in single quotes. The single quote is also useful if the value begins with a double-quote character. Conversely, the double quote can be used if the value begins with a single quote. If the value contains both single-quote and double-quote characters, the quote character used to enclose the value must be doubled each time it occurs within the value.

  • To include preceding or trailing spaces in the string value, the value must be enclosed in either single quotes or double quotes. Any leading or trailing spaces around integer, Boolean, or enumerated values are ignored, even if enclosed in quotes. However, spaces within a string literal keyword or value are preserved. Using .NET Framework version 1.1, single or double quotes may be used within a connection string without using delimiters (for example, Data Source= my'Server or Data Source= my"Server), unless a quote character is the first or last character in the value.

  • To include an equal sign (=) in a keyword or value, it must be preceded by another equal sign. For example, in the hypothetical connection string

    "key==word=value"

    the keyword is "key=word" and the value is "value".

  • If a specific keyword in a keyword= value pair occurs multiple times in a connection string, the last occurrence listed is used in the value set.

  • Keywords are not case sensitive.

The following table lists the valid names for keyword values within the ConnectionString.

NameDefaultDescription
Connect Timeout, Connection Timeout15The length of time (in seconds) to wait for a connection to the server before terminating the attempt and generating an error.
Host, Server, Data Source, DataSource, Address, Addr, Network AddresslocalhostThe name or network address of the instance of MySQL to which to connect. Multiple hosts can be specified separated by &. This can be useful where multiple MySQL servers are configured for replication and you are not concerned about the precise server you are connecting to. No attempt is made by the provider to synchronize writes to the database so care should be taken when using this option. In Unix environment with Mono, this can be a fully qualified path to MySQL socket filename. With this configuration, the Unix socket will be used instead of TCP/IP socket. Currently only a single socket name can be given so accessing MySQL in a replicated environment using Unix sockets is not currently supported.
Ignore PreparetrueWhen true, instructs the provider to ignore any calls to MySqlCommand.Prepare(). This option is provided to prevent issues with corruption of the statements when use with server side prepared statements. If you want to use server-side prepare statements, set this option to false. This option was added in Connector/NET 5.0.3 and Connector/NET 1.0.9.
Port3306The port MySQL is using to listen for connections. Specify -1 for this value to use a named pipe connection (Windows only). This value is ignored if Unix socket is used.
ProtocolsocketSpecifies the type of connection to make to the server.Values can be: socket or tcp for a socket connection pipe for a named pipe connection unix for a Unix socket connection memory to use MySQL shared memory
CharSet, Character Set Specifies the character set that should be used to encode all queries sent to the server. Resultsets are still returned in the character set of the data returned.
LoggingfalseWhen true, various pieces of information is output to any configured TraceListeners.
Allow BatchtrueWhen true, multiple SQL statements can be sent with one command execution. -Note- Starting with MySQL 4.1.1, batch statements should be separated by the server-defined separator character. Commands sent to earlier versions of MySQL should be separated with ';'.
EncryptfalseFor Connector/NET 5.0.3 and later, when true, SSL encryption is used for all data sent between the client and server if the server has a certificate installed. Recognized values are true, false, yes, and no. In versions before 5.0.3, this option had no effect.
Initial Catalog, DatabasemysqlThe name of the database to use intially
Password, pwd The password for the MySQL account being used.
Persist Security InfofalseWhen set to false or no (strongly recommended), security-sensitive information, such as the password, is not returned as part of the connection if the connection is open or has ever been in an open state. Resetting the connection string resets all connection string values including the password. Recognized values are true, false, yes, and no.
User Id, Username, Uid, User name The MySQL login account being used.
Shared Memory NameMYSQLThe name of the shared memory object to use for communication if the connection protocol is set to memory.
Allow Zero DatetimefalseTrue to have MySqlDataReader.GetValue() return a MySqlDateTime for date or datetime columns that have illegal values. False will cause a System.DateTime object to be returned for legal values and an exception will be thrown for illegal values.
Convert Zero DatetimefalseTrue to have MySqlDataReader.GetValue() and MySqlDataReader.GetDateTime() return DateTime.MinValue for date or datetime columns that have illegal values.
Old Syntax, OldSyntaxfalseAllows use of '@' symbol as a parameter marker. See MySqlCommand for more info. This option was deprecated in Connector/NET 5.2.2. All future code should be written using the '@' symbol.
Pipe Name, PipemysqlWhen set to the name of a named pipe, the MySqlConnection will attempt to connect to MySQL on that named pipe.This settings only applies to the Windows platform.
Procedure Cache25Sets the size of the stored procedure cache. By default, Connector/NET will store the metadata (input/output datatypes) about the last 25 stored procedures used. To disable the stored procedure cache, set the value to zero (0). This option was added in Connector/NET 5.0.2 and Connector/NET 1.0.9.
Use Procedure BodiestrueSetting this option to false indicates that the user connecting to the database does not have the SELECT privileges for the mysql.proc (stored procedures) table. When to set to false, Connector/NET will not rely on this information being available when the procedure is called. Because Connector/NET will be unable to determine this information, you should explicitly set the types of the all the parameters before the call and the parameters should be added to the command in the exact same order as they appear in the procedure definition. This option was added in Connector/NET 5.0.4 and Connector/NET 1.0.10.
default command timeout Sets the default value of the command timeout to be used. This does not supercede the individual command timeout property on an individual command object. If you set the command timeout property, that will be used. This option was added in Connector/NET 5.1.4
Treat Tiny As BooleantrueSetting this value to false indicates that TINYINT(1) will be treated as an INT. See also Section 10.1.1, “Overview of Numeric Types” for a further explanation of the TINYINT and BOOL data types.
Allow User VariablesfalseSetting this to true indicates that the provider expects user variables in the SQL. This option was added in Connector/NET version 5.2.2.

The following table lists the valid names for connection pooling values within the ConnectionString. For more information about connection pooling, see Connection Pooling for the MySQL Data Provider.

NameDefaultDescription
Connection Lifetime0When a connection is returned to the pool, its creation time is compared with the current time, and the connection is destroyed if that time span (in seconds) exceeds the value specified by Connection Lifetime. This is useful in clustered configurations to force load balancing between a running server and a server just brought online. A value of zero (0) causes pooled connections to have the maximum connection timeout.
Max Pool Size100The maximum number of connections allowed in the pool.
Min Pool Size0The minimum number of connections allowed in the pool.
PoolingtrueWhen true, the MySqlConnection object is drawn from the appropriate pool, or if necessary, is created and added to the appropriate pool. Recognized values are true, false, yes, and no.
Reset Pooled Connections, ResetConnections, ResetPooledConnectionstrueSpecifies whether a ping and a reset should be sent to the server before a pooled connection is returned. Not resetting will yield faster connection opens but also will not clear out session items such as temp tables.
Cache Server Configuration, CacheServerConfiguration, CacheServerConfigfalseSpecifies whether server variables should be updated when a pooled connection is returned. Turning this one will yeild faster opens but will also not catch any server changes made by other connections.

When setting keyword or connection pooling values that require a Boolean value, you can use 'yes' instead of 'true', and 'no' instead of 'false'.

Note

The MySQL Data Provider uses the native socket protocol to communicate with MySQL. Therefore, it does not support the use of an ODBC data source name (DSN) when connecting to MySQL because it does not add an ODBC layer.

Caution

In this release, the application should use caution when constructing a connection string based on user input (for example when retrieving user ID and password information from a dialog box, and appending it to the connection string). The application should ensure that a user cannot embed extra connection string parameters in these values (for example, entering a password as "validpassword;database=somedb" in an attempt to attach to a different database).

Examples

The following example creates a MySqlConnection and sets some of its properties

Visual Basic example:

  Public Sub CreateConnection()
    Dim myConnection As New MySqlConnection()
    myConnection.ConnectionString = "Persist Security Info=False;database=myDB;server=myHost;Connect Timeout=30;user id=myUser; pwd=myPass"
    myConnection.Open()
  End Sub 'CreateConnection
  

C# example:

  public void CreateConnection() 
  {
    MySqlConnection myConnection = new MySqlConnection();
    myConnection.ConnectionString = "Persist Security Info=False;database=myDB;server=myHost;Connect Timeout=30;user id=myUser; pwd=myPass";
    myConnection.Open();
  }
  

Examples

The following example creates a MySqlConnection in Unix environment with Mono installed. MySQL socket filename used in this example is "/var/lib/mysql/mysql.sock". The actual filename depends on your MySQL configuration.

Visual Basic example:

  Public Sub CreateConnection()
    Dim myConnection As New MySqlConnection()
    myConnection.ConnectionString = "database=myDB;server=/var/lib/mysql/mysql.sock;user id=myUser; pwd=myPass"
    myConnection.Open()
  End Sub 'CreateConnection
  

C# example:

  public void CreateConnection() 
  {
    MySqlConnection myConnection = new MySqlConnection();
    myConnection.ConnectionString = "database=myDB;server=/var/lib/mysql/mysql.sock;user id=myUser; pwd=myPass";
    myConnection.Open();
  }
  
27.2.3.3.4. Open

Opens a database connection with the property settings specified by the ConnectionString.

Exception: Cannot open a connection without specifying a data source or server.

Exception: A connection-level error occurred while opening the connection.

The MySqlConnection draws an open connection from the connection pool if one is available. Otherwise, it establishes a new connection to an instance of MySQL.

Examples

The following example creates a MySqlConnection, opens it, displays some of its properties, then closes the connection.

Visual Basic example:

Public Sub CreateMySqlConnection(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    MessageBox.Show("ServerVersion: " + myConnection.ServerVersion _
    + ControlChars.Cr + "State: " + myConnection.State.ToString())
    myConnection.Close()
End Sub
    

C# example:

public void CreateMySqlConnection(string myConnString) 
{
  MySqlConnection myConnection = new MySqlConnection(myConnString);
  myConnection.Open();
  MessageBox.Show("ServerVersion: " + myConnection.ServerVersion + 
          "\nState: " + myConnection.State.ToString());
  myConnection.Close();
}
    
27.2.3.3.5. Database

Gets the name of the current database or the database to be used after a connection is opened.

Returns: The name of the current database or the name of the database to be used after a connection is opened. The default value is an empty string.

The Database property does not update dynamically. If you change the current database using a SQL statement, then this property may reflect the wrong value. If you change the current database using the ChangeDatabase method, this property is updated to reflect the new database.

Examples

The following example creates a MySqlConnection and displays some of its read-only properties.

Visual Basic example:

Public Sub CreateMySqlConnection()
  Dim myConnString As String = _
    "Persist Security Info=False;database=test;server=localhost;user id=joeuser;pwd=pass"
  Dim myConnection As New MySqlConnection( myConnString )
  myConnection.Open()
  MessageBox.Show( "Server Version: " + myConnection.ServerVersion _
    + ControlChars.NewLine + "Database: " + myConnection.Database )
  myConnection.ChangeDatabase( "test2" )
  MessageBox.Show( "ServerVersion: " + myConnection.ServerVersion _ 
    + ControlChars.NewLine + "Database: " + myConnection.Database )
  myConnection.Close()
End Sub    
    

C# example:

public void CreateMySqlConnection()
{
  string myConnString = 
    "Persist Security Info=False;database=test;server=localhost;user id=joeuser;pwd=pass";
  MySqlConnection myConnection = new MySqlConnection( myConnString );
  myConnection.Open();
  MessageBox.Show( "Server Version: " + myConnection.ServerVersion 
    + "\nDatabase: " + myConnection.Database );
  myConnection.ChangeDatabase( "test2" );
  MessageBox.Show( "ServerVersion: " + myConnection.ServerVersion  
    + "\nDatabase: " + myConnection.Database );
  myConnection.Close();
}
    
27.2.3.3.6. State

Gets the current state of the connection.

Returns: A bitwise combination of the System.Data.ConnectionState values. The default is Closed.

The allowed state changes are:

  • From Closed to Open, using the Open method of the connection object.

  • From Open to Closed, using either the Close method or the Dispose method of the connection object.

Examples

The following example creates a MySqlConnection, opens it, displays some of its properties, then closes the connection.

Visual Basic example:

Public Sub CreateMySqlConnection(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    MessageBox.Show("ServerVersion: " + myConnection.ServerVersion _
    + ControlChars.Cr + "State: " + myConnection.State.ToString())
    myConnection.Close()
End Sub
    

C# example:

public void CreateMySqlConnection(string myConnString) 
{
  MySqlConnection myConnection = new MySqlConnection(myConnString);
  myConnection.Open();
  MessageBox.Show("ServerVersion: " + myConnection.ServerVersion + 
          "\nState: " + myConnection.State.ToString());
  myConnection.Close();
}
    
27.2.3.3.7. ServerVersion

Gets a string containing the version of the MySQL server to which the client is connected.

Returns: The version of the instance of MySQL.

Exception: The connection is closed.

Examples

The following example creates a MySqlConnection, opens it, displays some of its properties, then closes the connection.

Visual Basic example:

Public Sub CreateMySqlConnection(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    MessageBox.Show("ServerVersion: " + myConnection.ServerVersion _
    + ControlChars.Cr + "State: " + myConnection.State.ToString())
    myConnection.Close()
End Sub
    

C# example:

public void CreateMySqlConnection(string myConnString) 
{
  MySqlConnection myConnection = new MySqlConnection(myConnString);
  myConnection.Open();
  MessageBox.Show("ServerVersion: " + myConnection.ServerVersion + 
          "\nState: " + myConnection.State.ToString());
  myConnection.Close();
}
    
27.2.3.3.8. Close

Closes the connection to the database. This is the preferred method of closing any open connection.

The Close method rolls back any pending transactions. It then releases the connection to the connection pool, or closes the connection if connection pooling is disabled.

An application can call Close more than one time. No exception is generated.

Examples

The following example creates a MySqlConnection, opens it, displays some of its properties, then closes the connection.

Visual Basic example:

Public Sub CreateMySqlConnection(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    MessageBox.Show("ServerVersion: " + myConnection.ServerVersion _
    + ControlChars.Cr + "State: " + myConnection.State.ToString())
    myConnection.Close()
End Sub
    

C# example:

public void CreateMySqlConnection(string myConnString) 
{
  MySqlConnection myConnection = new MySqlConnection(myConnString);
  myConnection.Open();
  MessageBox.Show("ServerVersion: " + myConnection.ServerVersion + 
          "\nState: " + myConnection.State.ToString());
  myConnection.Close();
}
    
27.2.3.3.9. CreateCommand

Creates and returns a MySqlCommand object associated with the MySqlConnection.

Returns: A MySqlCommand object.

27.2.3.3.10. BeginTransaction

Begins a database transaction.

Returns: An object representing the new transaction.

Exception: Parallel transactions are not supported.

This command is equivalent to the MySQL BEGIN TRANSACTION command.

You must explicitly commit or roll back the transaction using the MySqlTransaction.Commit or MySqlTransaction.Rollback method.

Note

If you do not specify an isolation level, the default isolation level is used. To specify an isolation level with the BeginTransaction method, use the overload that takes the iso parameter.

Examples

The following example creates a MySqlConnection and a MySqlTransaction. It also demonstrates how to use the BeginTransaction, a MySqlTransaction.Commit, and MySqlTransaction.Rollback methods.

Visual Basic example:

Public Sub RunTransaction(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    
    Dim myCommand As MySqlCommand = myConnection.CreateCommand()
    Dim myTrans As MySqlTransaction
    
    ' Start a local transaction
    myTrans = myConnection.BeginTransaction()
    ' Must assign both transaction object and connection
    ' to Command object for a pending local transaction
    myCommand.Connection = myConnection
    myCommand.Transaction = myTrans
    
    Try
      myCommand.CommandText = "Insert into Test (id, desc) VALUES (100, 'Description')"
      myCommand.ExecuteNonQuery()
      myCommand.CommandText = "Insert into Test (id, desc) VALUES (101, 'Description')"
      myCommand.ExecuteNonQuery()
      myTrans.Commit()
      Console.WriteLine("Both records are written to database.")
    Catch e As Exception
      Try
        myTrans.Rollback()
      Catch ex As MySqlException
        If Not myTrans.Connection Is Nothing Then
          Console.WriteLine("An exception of type " + ex.GetType().ToString() + _
                            " was encountered while attempting to roll back the transaction.")
        End If
      End Try
    
      Console.WriteLine("An exception of type " + e.GetType().ToString() + _
                      "was encountered while inserting the data.")
      Console.WriteLine("Neither record was written to database.")
    Finally
      myConnection.Close()
    End Try
End Sub
    

C# example:

public void RunTransaction(string myConnString) 
{
  MySqlConnection myConnection = new MySqlConnection(myConnString);
  myConnection.Open();
  MySqlCommand myCommand = myConnection.CreateCommand();
  MySqlTransaction myTrans;
  // Start a local transaction
  myTrans = myConnection.BeginTransaction();
  // Must assign both transaction object and connection
  // to Command object for a pending local transaction
  myCommand.Connection = myConnection;
  myCommand.Transaction = myTrans;
    try
    {
      myCommand.CommandText = "insert into Test (id, desc) VALUES (100, 'Description')";
      myCommand.ExecuteNonQuery();
      myCommand.CommandText = "insert into Test (id, desc) VALUES (101, 'Description')";
      myCommand.ExecuteNonQuery();
      myTrans.Commit();
      Console.WriteLine("Both records are written to database.");
    }
    catch(Exception e)
    {
      try
      {
        myTrans.Rollback();
      }
      catch (SqlException ex)
      {
        if (myTrans.Connection != null)
        {
          Console.WriteLine("An exception of type " + ex.GetType() +
                            " was encountered while attempting to roll back the transaction.");
        }
      }
    
      Console.WriteLine("An exception of type " + e.GetType() +
                        " was encountered while inserting the data.");
      Console.WriteLine("Neither record was written to database.");
    }
    finally 
    {
      myConnection.Close();
    }
}
    
27.2.3.3.11. BeginTransaction1

Begins a database transaction with the specified isolation level.

Parameters: The isolation level under which the transaction should run.

Returns: An object representing the new transaction.

Exception: Parallel exceptions are not supported.

This command is equivalent to the MySQL BEGIN TRANSACTION command.

You must explicitly commit or roll back the transaction using the MySqlTransaction.Commit or MySqlTransaction.Rollback method.

Note

If you do not specify an isolation level, the default isolation level is used. To specify an isolation level with the BeginTransaction method, use the overload that takes the iso parameter.

Examples

The following example creates a MySqlConnection and a MySqlTransaction. It also demonstrates how to use the BeginTransaction, a MySqlTransaction.Commit, and MySqlTransaction.Rollback methods.

Visual Basic example:

Public Sub RunTransaction(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    
    Dim myCommand As MySqlCommand = myConnection.CreateCommand()
    Dim myTrans As MySqlTransaction
    
    ' Start a local transaction
    myTrans = myConnection.BeginTransaction()
    ' Must assign both transaction object and connection
    ' to Command object for a pending local transaction
    myCommand.Connection = myConnection
    myCommand.Transaction = myTrans
    
    Try
      myCommand.CommandText = "Insert into Test (id, desc) VALUES (100, 'Description')"
      myCommand.ExecuteNonQuery()
      myCommand.CommandText = "Insert into Test (id, desc) VALUES (101, 'Description')"
      myCommand.ExecuteNonQuery()
      myTrans.Commit()
      Console.WriteLine("Both records are written to database.")
    Catch e As Exception
      Try
        myTrans.Rollback()
      Catch ex As MySqlException
        If Not myTrans.Connection Is Nothing Then
          Console.WriteLine("An exception of type " + ex.GetType().ToString() + _
                            " was encountered while attempting to roll back the transaction.")
        End If
      End Try
    
      Console.WriteLine("An exception of type " + e.GetType().ToString() + _
                      "was encountered while inserting the data.")
      Console.WriteLine("Neither record was written to database.")
    Finally
      myConnection.Close()
    End Try
End Sub
    

C# example:

public void RunTransaction(string myConnString) 
{
  MySqlConnection myConnection = new MySqlConnection(myConnString);
  myConnection.Open();
  MySqlCommand myCommand = myConnection.CreateCommand();
  MySqlTransaction myTrans;
  // Start a local transaction
  myTrans = myConnection.BeginTransaction();
  // Must assign both transaction object and connection
  // to Command object for a pending local transaction
  myCommand.Connection = myConnection;
  myCommand.Transaction = myTrans;
    try
    {
      myCommand.CommandText = "insert into Test (id, desc) VALUES (100, 'Description')";
      myCommand.ExecuteNonQuery();
      myCommand.CommandText = "insert into Test (id, desc) VALUES (101, 'Description')";
      myCommand.ExecuteNonQuery();
      myTrans.Commit();
      Console.WriteLine("Both records are written to database.");
    }
    catch(Exception e)
    {
      try
      {
        myTrans.Rollback();
      }
      catch (SqlException ex)
      {
        if (myTrans.Connection != null)
        {
          Console.WriteLine("An exception of type " + ex.GetType() +
                            " was encountered while attempting to roll back the transaction.");
        }
      }
    
      Console.WriteLine("An exception of type " + e.GetType() +
                        " was encountered while inserting the data.");
      Console.WriteLine("Neither record was written to database.");
    }
    finally 
    {
      myConnection.Close();
    }
}
    
27.2.3.3.12. ChangeDatabase

Changes the current database for an open MySqlConnection.

Parameters: The name of the database to use.

The value supplied in the database parameter must be a valid database name. The database parameter cannot contain a null value, an empty string, or a string with only blank characters.

When you are using connection pooling against MySQL, and you close the connection, it is returned to the connection pool. The next time the connection is retrieved from the pool, the reset connection request executes before the user performs any operations.

MySQL Enterprise MySQL Enterprise subscribers will find more information on this subject in the Knowledge Base article, Understanding and Using Connection Pooling. Access to the MySQL Knowledge Base collection of articles is one of the advantages of subscribing to MySQL Enterprise. To subscribe see http://www.mysql.com/products/enterprise/advisors.html.

Exception: The database name is not valid.

Exception: The connection is not open.

Exception: Cannot change the database.

Examples

The following example creates a MySqlConnection and displays some of its read-only properties.

Visual Basic example:

Public Sub CreateMySqlConnection()
  Dim myConnString As String = _
    "Persist Security Info=False;database=test;server=localhost;user id=joeuser;pwd=pass"
  Dim myConnection As New MySqlConnection( myConnString )
  myConnection.Open()
  MessageBox.Show( "Server Version: " + myConnection.ServerVersion _
    + ControlChars.NewLine + "Database: " + myConnection.Database )
  myConnection.ChangeDatabase( "test2" )
  MessageBox.Show( "ServerVersion: " + myConnection.ServerVersion _ 
    + ControlChars.NewLine + "Database: " + myConnection.Database )
  myConnection.Close()
End Sub    
    

C# example:

public void CreateMySqlConnection()
{
  string myConnString = 
    "Persist Security Info=False;database=test;server=localhost;user id=joeuser;pwd=pass";
  MySqlConnection myConnection = new MySqlConnection( myConnString );
  myConnection.Open();
  MessageBox.Show( "Server Version: " + myConnection.ServerVersion 
    + "\nDatabase: " + myConnection.Database );
  myConnection.ChangeDatabase( "test2" );
  MessageBox.Show( "ServerVersion: " + myConnection.ServerVersion  
    + "\nDatabase: " + myConnection.Database );
  myConnection.Close();
}
    
27.2.3.3.13. StateChange

Occurs when the state of the connection changes.

The StateChange event fires whenever the State changes from closed to opened, or from opened to closed. StateChange fires immediately after the MySqlConnection transitions.

If an event handler throws an exception from within the StateChange event, the exception propagates to the caller of the Open or Close method.

The StateChange event is not raised unless you explicitly call Close or Dispose.

The event handler receives an argument of type System.Data.StateChangeEventArgs containing data related to this event. The following StateChangeEventArgs properties provide information specific to this event.

PropertyDescription
System.Data.StateChangeEventArgs.CurrentState Gets the new state of the connection. The connection object will be in the new state already when the event is fired.
System.Data.StateChangeEventArgs.OriginalState Gets the original state of the connection.
27.2.3.3.14. InfoMessage

Occurs when MySQL returns warnings as a result of executing a command or query.

27.2.3.3.15. ConnectionTimeout

Gets the time to wait while trying to establish a connection before terminating the attempt and generating an error.

Exception: The value set is less than 0.

A value of 0 indicates no limit, and should be avoided in a MySqlConnection.ConnectionString because an attempt to connect will wait indefinitely.

Examples

The following example creates a MySqlConnection and sets some of its properties in the connection string.

Visual Basic example:

Public Sub CreateSqlConnection()
  Dim myConnection As New MySqlConnection()
  myConnection.ConnectionString = "Persist Security Info=False;Username=user;Password=pass;database=test1;server=localhost;Connect Timeout=30"
  myConnection.Open()
End Sub

C# example:

public void CreateSqlConnection() 
{
  MySqlConnection myConnection = new MySqlConnection();
  myConnection.ConnectionString = "Persist Security Info=False;Username=user;»
      Password=pass;database=test1;server=localhost;Connect Timeout=30";
  myConnection.Open();
}

27.2.3.4. Using MySqlDataAdapter

Represents a set of data commands and a database connection that are used to fill a data set and update a MySQL database. This class cannot be inherited.

The MySQLDataAdapter, serves as a bridge between a System.Data.DataSet and MySQL for retrieving and saving data. The MySQLDataAdapter provides this bridge by mapping DbDataAdapter.Fill, which changes the data in the DataSet to match the data in the data source, and DbDataAdapter.Update, which changes the data in the data source to match the data in the DataSet, using the appropriate SQL statements against the data source.

When the MySQLDataAdapter fills a DataSet, it will create the necessary tables and columns for the returned data if they do not already exist. However, primary key information will not be included in the implicitly created schema unless the System.Data.MissingSchemaAction property is set to System.Data.MissingSchemaAction.AddWithKey. You may also have the MySQLDataAdapter create the schema of the DataSet, including primary key information, before filling it with data using System.Data.Common.DbDataAdapter.FillSchema.

MySQLDataAdapter is used in conjunction with MySqlConnection and MySqlCommand to increase performance when connecting to a MySQL database.

The MySQLDataAdapter also includes the MySqlDataAdapter.SelectCommand, MySqlDataAdapter.InsertCommand, MySqlDataAdapter.DeleteCommand, MySqlDataAdapter.UpdateCommand, and DataAdapter.TableMappings properties to facilitate the loading and updating of data.

When an instance of MySQLDataAdapter is created, the read/write properties are set to initial values. For a list of these values, see the MySQLDataAdapter constructor.

Note

Please be aware that the DataColumn class in .NET only allows columns with type of Int16, Int32, or Int64 to be autoincrement columns. If you plan to use autoincremement columns with MySQL, you should consider using signed integer columns.

Examples

The following example creates a MySqlCommand and a MySqlConnection. The MySqlConnection is opened and set as the MySqlCommand.Connection for the MySqlCommand. The example then calls MySqlCommand.ExecuteNonQuery, and closes the connection. To accomplish this, the ExecuteNonQuery is passed a connection string and a query string that is a SQL INSERT statement.

Visual Basic example:

Public Function SelectRows(dataSet As DataSet, connection As String, query As String) As DataSet
    Dim conn As New MySqlConnection(connection)
    Dim adapter As New MySqlDataAdapter()
    adapter.SelectCommand = new MySqlCommand(query, conn)
    adapter.Fill(dataset)
    Return dataset
End Function
  

C# example:

public DataSet SelectRows(DataSet dataset,string connection,string query) 
{
    MySqlConnection conn = new MySqlConnection(connection);
    MySqlDataAdapter adapter = new MySqlDataAdapter();
    adapter.SelectCommand = new MySqlCommand(query, conn);
    adapter.Fill(dataset);
    return dataset;
}
  
27.2.3.4.1. Class MySqlDataAdapter Constructor

Overload methods for MySqlDataAdapter

Initializes a new instance of the MySqlDataAdapter class.

When an instance of MySqlDataAdapter is created, the following read/write properties are set to the following initial values.

Properties Initial Value
MissingMappingAction MissingMappingAction.Passthrough
MissingSchemaAction MissingSchemaAction.Add

You can change the value of any of these properties through a separate call to the property.

Examples

The following example creates a MySqlDataAdapter and sets some of its properties.

Visual Basic example:

 
Public Sub CreateSqlDataAdapter()
    Dim conn As MySqlConnection = New MySqlConnection("Data Source=localhost;" & _
    "database=test")
    Dim da As MySqlDataAdapter = New MySqlDataAdapter
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey    
   
    da.SelectCommand = New MySqlCommand("SELECT id, name FROM mytable", conn)
    da.InsertCommand = New MySqlCommand("INSERT INTO mytable (id, name) " & _
                                            "VALUES (@id, @name)", conn)
    da.UpdateCommand = New MySqlCommand("UPDATE mytable SET id=@id, name=@name " & _
                                            "WHERE id=@oldId", conn)
    da.DeleteCommand = New MySqlCommand("DELETE FROM mytable WHERE id=@id", conn)
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
End Sub

C# example:

public static void CreateSqlDataAdapter() 
{
    MySqlConnection conn = new MySqlConnection("Data Source=localhost;database=test");
    MySqlDataAdapter da = new MySqlDataAdapter();
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey;
   
    da.SelectCommand = new MySqlCommand("SELECT id, name FROM mytable", conn);
    da.InsertCommand = new MySqlCommand("INSERT INTO mytable (id, name) " +
                                            "VALUES (@id, @name)", conn);
    da.UpdateCommand = new MySqlCommand("UPDATE mytable SET id=@id, name=@name " +
                                            "WHERE id=@oldId", conn);
    da.DeleteCommand = new MySqlCommand("DELETE FROM mytable WHERE id=@id", conn);
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
}  
27.2.3.4.2. Class MySqlDataAdapter Constructor Form 1

Initializes a new instance of the MySqlDataAdapter class with the specified MySqlCommand as the SelectCommand property.

Parameters: MySqlCommand that is a SQL SELECT statement or stored procedure and is set as the SelectCommand property of the MySqlDataAdapter.

When an instance of MySqlDataAdapter is created, the following read/write properties are set to the following initial values.

Properties Initial Value
MissingMappingAction MissingMappingAction.Passthrough
MissingSchemaAction MissingSchemaAction.Add

You can change the value of any of these properties through a separate call to the property.

When SelectCommand (or any of the other command properties) is assigned to a previously created MySqlCommand, the MySqlCommand is not cloned. The SelectCommand maintains a reference to the previously created MySqlCommand object.

Examples

The following example creates a MySqlDataAdapter and sets some of its properties.

Visual Basic example:

 
Public Sub CreateSqlDataAdapter()
    Dim conn As MySqlConnection = New MySqlConnection("Data Source=localhost;" & _
    "database=test")
  Dim cmd as new MySqlCommand("SELECT id, name FROM mytable", conn)
    Dim da As MySqlDataAdapter = New MySqlDataAdapter(cmd)
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey    
   
    da.InsertCommand = New MySqlCommand("INSERT INTO mytable (id, name) " & _
                                            "VALUES (@id, @name)", conn)
    da.UpdateCommand = New MySqlCommand("UPDATE mytable SET id=@id, name=@name " & _
                                            "WHERE id=@oldId", conn)
    da.DeleteCommand = New MySqlCommand("DELETE FROM mytable WHERE id=@id", conn)
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
End Sub

C# example:

public static void CreateSqlDataAdapter() 
{
    MySqlConnection conn = new MySqlConnection("Data Source=localhost;database=test");
    MySqlCommand cmd = new MySqlCommand("SELECT id, name FROM mytable", conn);
    MySqlDataAdapter da = new MySqlDataAdapter(cmd);
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey;
   
    da.InsertCommand = new MySqlCommand("INSERT INTO mytable (id, name) " +
                                            "VALUES (@id, @name)", conn);
    da.UpdateCommand = new MySqlCommand("UPDATE mytable SET id=@id, name=@name " +
                                            "WHERE id=@oldId", conn);
    da.DeleteCommand = new MySqlCommand("DELETE FROM mytable WHERE id=@id", conn);
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
}  
27.2.3.4.3. Class MySqlDataAdapter Constructor Form 2

Initializes a new instance of the MySqlDataAdapter class with a SelectCommand and a MySqlConnection object.

Parameters: A String that is a SQL SELECT statement or stored procedure to be used by the SelectCommand property of the MySqlDataAdapter.

Parameters: A MySqlConnection that represents the connection.

This implementation of the MySqlDataAdapter opens and closes a MySqlConnection if it is not already open. This can be useful in a an application that must call the DbDataAdapter.Fill method for two or more MySqlDataAdapter objects. If the MySqlConnection is already open, you must explicitly call MySqlConnection.Close or MySqlConnection.Dispose to close it.

When an instance of MySqlDataAdapter is created, the following read/write properties are set to the following initial values.

Properties Initial Value
MissingMappingAction MissingMappingAction.Passthrough
MissingSchemaAction MissingSchemaAction.Add

You can change the value of any of these properties through a separate call to the property.

Examples

The following example creates a MySqlDataAdapter and sets some of its properties.

Visual Basic example:

 
Public Sub CreateSqlDataAdapter()
    Dim conn As MySqlConnection = New MySqlConnection("Data Source=localhost;" & _
    "database=test")
    Dim da As MySqlDataAdapter = New MySqlDataAdapter("SELECT id, name FROM mytable", conn)
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey    
   
    da.InsertCommand = New MySqlCommand("INSERT INTO mytable (id, name) " & _
                                            "VALUES (@id, @name)", conn)
    da.UpdateCommand = New MySqlCommand("UPDATE mytable SET id=@id, name=@name " & _
                                            "WHERE id=@oldId", conn)
    da.DeleteCommand = New MySqlCommand("DELETE FROM mytable WHERE id=@id", conn)
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
End Sub

C# example:

public static void CreateSqlDataAdapter() 
{
    MySqlConnection conn = new MySqlConnection("Data Source=localhost;database=test");
    MySqlDataAdapter da = new MySqlDataAdapter("SELECT id, name FROM mytable", conn);
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey;
   
    da.InsertCommand = new MySqlCommand("INSERT INTO mytable (id, name) " +
                                            "VALUES (@id, @name)", conn);
    da.UpdateCommand = new MySqlCommand("UPDATE mytable SET id=@id, name=@name " +
                                            "WHERE id=@oldId", conn);
    da.DeleteCommand = new MySqlCommand("DELETE FROM mytable WHERE id=@id", conn);
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
}  
27.2.3.4.4. Class MySqlDataAdapter Constructor Form 3

Initializes a new instance of the MySqlDataAdapter class with a SelectCommand and a connection string.

Parameters: A string that is a SQL SELECT statement or stored procedure to be used by the SelectCommand property of the MySqlDataAdapter.

Parameters: The connection string

When an instance of MySqlDataAdapter is created, the following read/write properties are set to the following initial values.

Properties Initial Value
MissingMappingAction MissingMappingAction.Passthrough
MissingSchemaAction MissingSchemaAction.Add

You can change the value of any of these properties through a separate call to the property.

Examples

The following example creates a MySqlDataAdapter and sets some of its properties.

Visual Basic example:

 
Public Sub CreateSqlDataAdapter()
    Dim da As MySqlDataAdapter = New MySqlDataAdapter("SELECT id, name FROM mytable", "Data Source=localhost;database=test")
    Dim conn As MySqlConnection = da.SelectCommand.Connection
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey    
   
    da.InsertCommand = New MySqlCommand("INSERT INTO mytable (id, name) " & _
                                            "VALUES (@id, @name)", conn)
    da.UpdateCommand = New MySqlCommand("UPDATE mytable SET id=@id, name=@name " & _
                                            "WHERE id=@oldId", conn)
    da.DeleteCommand = New MySqlCommand("DELETE FROM mytable WHERE id=@id", conn)
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name")
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original
End Sub

C# example:

public static void CreateSqlDataAdapter() 
{
    MySqlDataAdapter da = new MySqlDataAdapter("SELECT id, name FROM mytable", "Data Source=localhost;database=test");
    MySqlConnection conn = da.SelectCommand.Connection;
    da.MissingSchemaAction = MissingSchemaAction.AddWithKey;
   
    da.InsertCommand = new MySqlCommand("INSERT INTO mytable (id, name) " +
                                            "VALUES (@id, @name)", conn);
    da.UpdateCommand = new MySqlCommand("UPDATE mytable SET id=@id, name=@name " +
                                            "WHERE id=@oldId", conn);
    da.DeleteCommand = new MySqlCommand("DELETE FROM mytable WHERE id=@id", conn);
    da.InsertCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.InsertCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
 
    da.UpdateCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
    da.UpdateCommand.Parameters.Add("@name", MySqlDbType.VarChar, 40, "name");
    da.UpdateCommand.Parameters.Add("@oldId", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
    da.DeleteCommand.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id").SourceVersion = DataRowVersion.Original;
}  
27.2.3.4.5. DeleteCommand

Gets or sets a SQL statement or stored procedure used to delete records from the data set.

Value: A MySqlCommand used during System.Data.Common.DataAdapter.Update to delete records in the database that correspond to deleted rows in the DataSet.

During System.Data.Common.DataAdapter.Update, if this property is not set and primary key information is present in the DataSet, the DeleteCommand can be generated automatically if you set the SelectCommand property and use the MySqlCommandBuilder. Then, any additional commands that you do not set are generated by the MySqlCommandBuilder. This generation logic requires key column information to be present in the DataSet.

When DeleteCommand is assigned to a previously created MySqlCommand, the MySqlCommand is not cloned. The DeleteCommand maintains a reference to the previously created MySqlCommand object.

Examples

The following example creates a MySqlDataAdapter and sets the SelectCommand and DeleteCommand properties. It assumes you have already created a MySqlConnection object.

Visual Basic example:

Public Shared Function CreateCustomerAdapter(conn As MySqlConnection) As MySqlDataAdapter 
  
  Dim da As MySqlDataAdapter = New MySqlDataAdapter()
  Dim cmd As MySqlCommand
  Dim parm As MySqlParameter
  ' Create the SelectCommand.
  cmd = New MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn)
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15)
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15)
  da.SelectCommand = cmd
  ' Create the DeleteCommand.
  cmd = New MySqlCommand("DELETE FROM mytable WHERE id=@id", conn)
  parm = cmd.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id")
  parm.SourceVersion = DataRowVersion.Original
  da.DeleteCommand = cmd
  Return da
End Function

C# example:

public static MySqlDataAdapter CreateCustomerAdapter(MySqlConnection conn)
{
  MySqlDataAdapter da = new MySqlDataAdapter();
  MySqlCommand cmd;
  MySqlParameter parm;
  // Create the SelectCommand.
  cmd = new MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn);
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15);
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15);
  da.SelectCommand = cmd;
  // Create the DeleteCommand.
  cmd = new MySqlCommand("DELETE FROM mytable WHERE id=@id", conn);
  parm = cmd.Parameters.Add("@id", MySqlDbType.VarChar, 5, "id");
  parm.SourceVersion = DataRowVersion.Original;
  da.DeleteCommand = cmd;
  return da;
}
27.2.3.4.6. InsertCommand

Gets or sets a SQL statement or stored procedure used to insert records into the data set.

Value: A MySqlCommand used during System.Data.Common.DataAdapter.Update to insert records into the database that correspond to new rows in the DataSet.

During System.Data.Common.DataAdapter.Update, if this property is not set and primary key information is present in the DataSet, the InsertCommand can be generated automatically if you set the SelectCommand property and use the MySqlCommandBuilder. Then, any additional commands that you do not set are generated by the MySqlCommandBuilder. This generation logic requires key column information to be present in the DataSet.

When InsertCommand is assigned to a previously created MySqlCommand, the MySqlCommand is not cloned. The InsertCommand maintains a reference to the previously created MySqlCommand object.

Note

If execution of this command returns rows, these rows may be added to the DataSet depending on how you set the MySqlCommand.UpdatedRowSource property of the MySqlCommand object.

Examples

The following example creates a MySqlDataAdapter and sets the SelectCommand and InsertCommand properties. It assumes you have already created a MySqlConnection object.

Visual Basic example:

Public Shared Function CreateCustomerAdapter(conn As MySqlConnection) As MySqlDataAdapter 
  
  Dim da As MySqlDataAdapter = New MySqlDataAdapter()
  Dim cmd As MySqlCommand
  Dim parm As MySqlParameter
  ' Create the SelectCommand.
  cmd = New MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn)
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15)
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15)
  da.SelectCommand = cmd
  ' Create the InsertCommand.
  cmd = New MySqlCommand("INSERT INTO mytable (id,name) VALUES (@id, @name)", conn)
  cmd.Parameters.Add( "@id", MySqlDbType.VarChar, 15, "id" )
  cmd.Parameters.Add( "@name", MySqlDbType.VarChar, 15, "name" )  
  da.InsertCommand = cmd
  
  Return da
End Function

C# example:

public static MySqlDataAdapter CreateCustomerAdapter(MySqlConnection conn)
{
  MySqlDataAdapter da = new MySqlDataAdapter();
  MySqlCommand cmd;
  MySqlParameter parm;
  // Create the SelectCommand.
  cmd = new MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn);
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15);
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15);
  da.SelectCommand = cmd;
  // Create the InsertCommand.
  cmd = new MySqlCommand("INSERT INTO mytable (id,name) VALUES (@id,@name)", conn);
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15, "id" );
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15, "name" );
  
  da.InsertCommand = cmd;  
  return da;
}
27.2.3.4.7. UpdateCommand

Gets or sets a SQL statement or stored procedure used to updated records in the data source.

Value: A MySqlCommand used during System.Data.Common.DataAdapter.Update to update records in the database with data from the DataSet.

During System.Data.Common.DataAdapter.Update, if this property is not set and primary key information is present in the DataSet, the UpdateCommand can be generated automatically if you set the SelectCommand property and use the MySqlCommandBuilder. Then, any additional commands that you do not set are generated by the MySqlCommandBuilder. This generation logic requires key column information to be present in the DataSet.

When UpdateCommand is assigned to a previously created MySqlCommand, the MySqlCommand is not cloned. The UpdateCommand maintains a reference to the previously created MySqlCommand object.

Note

If execution of this command returns rows, these rows may be merged with the DataSet depending on how you set the MySqlCommand.UpdatedRowSource property of the MySqlCommand object.

Examples

The following example creates a MySqlDataAdapter and sets the SelectCommand and UpdateCommand properties. It assumes you have already created a MySqlConnection object.

Visual Basic example:

Public Shared Function CreateCustomerAdapter(conn As MySqlConnection) As MySqlDataAdapter 
  
  Dim da As MySqlDataAdapter = New MySqlDataAdapter()
  Dim cmd As MySqlCommand
  Dim parm As MySqlParameter
  ' Create the SelectCommand.
  cmd = New MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn)
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15)
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15)
  da.SelectCommand = cmd
  ' Create the UpdateCommand.
  cmd = New MySqlCommand("UPDATE mytable SET id=@id, name=@name WHERE id=@oldId", conn)
  cmd.Parameters.Add( "@id", MySqlDbType.VarChar, 15, "id" )
  cmd.Parameters.Add( "@name", MySqlDbType.VarChar, 15, "name" )  
  
  parm = cmd.Parameters.Add("@oldId", MySqlDbType.VarChar, 15, "id")
  parm.SourceVersion = DataRowVersion.Original
  
  da.UpdateCommand = cmd
  
  Return da
End Function

C# example:

public static MySqlDataAdapter CreateCustomerAdapter(MySqlConnection conn)
{
  MySqlDataAdapter da = new MySqlDataAdapter();
  MySqlCommand cmd;
  MySqlParameter parm;
  // Create the SelectCommand.
  cmd = new MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn);
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15);
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15);
  da.SelectCommand = cmd;
  // Create the UpdateCommand.
  cmd = new MySqlCommand("UPDATE mytable SET id=@id, name=@name WHERE id=@oldId", conn);
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15, "id" );
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15, "name" );
  
  parm = cmd.Parameters.Add( "@oldId", MySqlDbType.VarChar, 15, "id" );
  parm.SourceVersion = DataRowVersion.Original;
  
  da.UpdateCommand = cmd;  
  return da;
}
27.2.3.4.8. SelectCommand

Gets or sets a SQL statement or stored procedure used to select records in the data source.

Value: A MySqlCommand used during System.Data.Common.DbDataAdapter.Fill to select records from the database for placement in the DataSet.

When SelectCommand is assigned to a previously created MySqlCommand, the MySqlCommand is not cloned. The SelectCommand maintains a reference to the previously created MySqlCommand object.

If the SelectCommand does not return any rows, no tables are added to the DataSet, and no exception is raised.

Examples

The following example creates a MySqlDataAdapter and sets the SelectCommand and InsertCommand properties. It assumes you have already created a MySqlConnection object.

Visual Basic example:

Public Shared Function CreateCustomerAdapter(conn As MySqlConnection) As MySqlDataAdapter 
  
  Dim da As MySqlDataAdapter = New MySqlDataAdapter()
  Dim cmd As MySqlCommand
  Dim parm As MySqlParameter
  ' Create the SelectCommand.
  cmd = New MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn)
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15)
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15)
  da.SelectCommand = cmd
  ' Create the InsertCommand.
  cmd = New MySqlCommand("INSERT INTO mytable (id,name) VALUES (@id, @name)", conn)
  cmd.Parameters.Add( "@id", MySqlDbType.VarChar, 15, "id" )
  cmd.Parameters.Add( "@name", MySqlDbType.VarChar, 15, "name" )  
  da.InsertCommand = cmd
  
  Return da
End Function

C# example:

public static MySqlDataAdapter CreateCustomerAdapter(MySqlConnection conn)
{
  MySqlDataAdapter da = new MySqlDataAdapter();
  MySqlCommand cmd;
  MySqlParameter parm;
  // Create the SelectCommand.
  cmd = new MySqlCommand("SELECT * FROM mytable WHERE id=@id AND name=@name", conn);
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15);
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15);
  da.SelectCommand = cmd;
  // Create the InsertCommand.
  cmd = new MySqlCommand("INSERT INTO mytable (id,name) VALUES (@id,@name)", conn);
  cmd.Parameters.Add("@id", MySqlDbType.VarChar, 15, "id" );
  cmd.Parameters.Add("@name", MySqlDbType.VarChar, 15, "name" );
  
  da.InsertCommand = cmd;  
  return da;
}

27.2.3.5. Using MySqlDataReader

To create a MySQLDataReader, you must call the MySqlCommand.ExecuteReader method of the MySqlCommand object, rather than directly using a constructor.

While the MySqlDataReader is in use, the associated MySqlConnection is busy serving the MySqlDataReader, and no other operations can be performed on the MySqlConnection other than closing it. This is the case until the MySqlDataReader.Close method of the MySqlDataReader is called.

MySqlDataReader.IsClosed and MySqlDataReader.RecordsAffected are the only properties that you can call after the MySqlDataReader is closed. Though the RecordsAffected property may be accessed at any time while the MySqlDataReader exists, always call Close before returning the value of RecordsAffected to ensure an accurate return value.

For optimal performance, MySqlDataReader avoids creating unnecessary objects or making unnecessary copies of data. As a result, multiple calls to methods such as MySqlDataReader.GetValue return a reference to the same object. Use caution if you are modifying the underlying value of the objects returned by methods such as GetValue.

Examples

The following example creates a MySqlConnection, a MySqlCommand, and a MySqlDataReader. The example reads through the data, writing it out to the console. Finally, the example closes the MySqlDataReader, then the MySqlConnection.

Visual Basic example:

Public Sub ReadMyData(myConnString As String)
    Dim mySelectQuery As String = "SELECT OrderID, CustomerID FROM Orders"
    Dim myConnection As New MySqlConnection(myConnString)
    Dim myCommand As New MySqlCommand(mySelectQuery, myConnection)
    myConnection.Open()
    Dim myReader As MySqlDataReader
    myReader = myCommand.ExecuteReader()
    ' Always call Read before accessing data.
    While myReader.Read()
        Console.WriteLine((myReader.GetInt32(0) & ", " & myReader.GetString(1)))
    End While
    ' always call Close when done reading.
    myReader.Close()
    ' Close the connection when done with it.
    myConnection.Close()
End Sub 'ReadMyData
  

C# example:

public void ReadMyData(string myConnString) {
    string mySelectQuery = "SELECT OrderID, CustomerID FROM Orders";
    MySqlConnection myConnection = new MySqlConnection(myConnString);
    MySqlCommand myCommand = new MySqlCommand(mySelectQuery,myConnection);
    myConnection.Open();
    MySqlDataReader myReader;
    myReader = myCommand.ExecuteReader();
    // Always call Read before accessing data.
    while (myReader.Read()) {
       Console.WriteLine(myReader.GetInt32(0) + ", " + myReader.GetString(1));
    }
    // always call Close when done reading.
    myReader.Close();
    // Close the connection when done with it.
    myConnection.Close();
 }
  
27.2.3.5.1. GetBytes

GetBytes returns the number of available bytes in the field. In most cases this is the exact length of the field. However, the number returned may be less than the true length of the field if GetBytes has already been used to obtain bytes from the field. This may be the case, for example, if the MySqlDataReader is reading a large data structure into a buffer. For more information, see the SequentialAccess setting for MySqlCommand.CommandBehavior.

If you pass a buffer that is a null reference (Nothing in Visual Basic), GetBytes returns the length of the field in bytes.

No conversions are performed; therefore the data retrieved must already be a byte array.

27.2.3.5.2. GetTimeSpan

Gets the value of the specified column as a TimeSpan object.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.3. GetDateTime

Gets the value of the specified column as a System.DateTime object.

Note

MySQL allows date columns to contain the value '0000-00-00' and datetime columns to contain the value '0000-00-00 00:00:00'. The DateTime structure cannot contain or represent these values. To read a datetime value from a column that might contain zero values, use GetMySqlDateTime. The behavior of reading a zero datetime column using this method is defined by the ZeroDateTimeBehavior connection string option. For more information on this option, please refer to MySqlConnection.ConnectionString.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.4. GetMySqlDateTime

Gets the value of the specified column as a MySql.Data.Types.MySqlDateTime object.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.5. GetString

Gets the value of the specified column as a String object.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.6. GetDecimal

Gets the value of the specified column as a Decimal object.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.7. GetDouble

Gets the value of the specified column as a double-precision floating point number.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.8. GetFloat

Gets the value of the specified column as a single-precision floating point number.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.9. GetGiud

Gets the value of the specified column as a globally-unique identifier (GUID).

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.10. GetInt16

Gets the value of the specified column as a 16-bit signed integer.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.11. GetInt32

Gets the value of the specified column as a 32-bit signed integer.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.12. GetInt64

Gets the value of the specified column as a 64-bit signed integer.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.13. GetUInt16

Gets the value of the specified column as a 16-bit unsigned integer.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.14. GetUInt32

Gets the value of the specified column as a 32-bit unsigned integer.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.5.15. GetUInt64

Gets the value of the specified column as a 64-bit unsigned integer.

Parameters: The zero-based column ordinal.

Returns: The value of the specified column.

27.2.3.6. Using MySqlException

This class is created whenever the MySQL Data Provider encounters an error generated from the server.

Any open connections are not automatically closed when an exception is thrown. If the client application determines that the exception is fatal, it should close any open MySqlDataReader objects or MySqlConnection objects.

Examples

The following example generates a MySqlException due to a missing server, and then displays the exception.

Visual Basic example:

Public Sub ShowException()
     Dim mySelectQuery As String = "SELECT column1 FROM table1"
     Dim myConnection As New MySqlConnection ("Data Source=localhost;Database=Sample;")
     Dim myCommand As New MySqlCommand(mySelectQuery, myConnection)
     Try
         myCommand.Connection.Open()
     Catch e As MySqlException
    MessageBox.Show( e.Message )
     End Try
 End Sub
  

C# example:

public void ShowException() 
{
   string mySelectQuery = "SELECT column1 FROM table1";
   MySqlConnection myConnection =
      new MySqlConnection("Data Source=localhost;Database=Sample;");
   MySqlCommand myCommand = new MySqlCommand(mySelectQuery,myConnection);
   try 
   {
      myCommand.Connection.Open();
   }
   catch (MySqlException e) 
   {
    MessageBox.Show( e.Message );
   }
}
  

27.2.3.7. Using MySqlParameter

Parameter names are not case sensitive.

Examples

The following example creates multiple instances of MySqlParameter through the MySqlParameterCollection collection within the MySqlDataAdapter. These parameters are used to select data from the data source and place the data in the DataSet. This example assumes that a DataSet and a MySqlDataAdapter have already been created with the appropriate schema, commands, and connection.

Visual Basic example:

Public Sub AddSqlParameters()
    ' ...
    ' create myDataSet and myDataAdapter
    ' ...
    myDataAdapter.SelectCommand.Parameters.Add("@CategoryName", MySqlDbType.VarChar, 80).Value = "toasters"
    myDataAdapter.SelectCommand.Parameters.Add("@SerialNum", MySqlDbType.Long).Value = 239
    
    myDataAdapter.Fill(myDataSet)
End Sub 'AddSqlParameters 
  

C# example:

public void AddSqlParameters() 
{
// ...
// create myDataSet and myDataAdapter
// ...
  myDataAdapter.SelectCommand.Parameters.Add("@CategoryName", MySqlDbType.VarChar, 80).Value = "toasters";
  myDataAdapter.SelectCommand.Parameters.Add("@SerialNum", MySqlDbType.Long).Value = 239;
  myDataAdapter.Fill(myDataSet);
}
  

27.2.3.8. Using MySqlParameterCollection

The number of the parameters in the collection must be equal to the number of parameter placeholders within the command text, or an exception will be generated.

Examples

The following example creates multiple instances of MySqlParameter through the MySqlParameterCollection collection within the MySqlDataAdapter. These parameters are used to select data within the data source and place the data in the DataSet. This code assumes that a DataSet and a MySqlDataAdapter have already been created with the appropriate schema, commands, and connection.

Visual Basic example:

Public Sub AddParameters()
    ' ...
    ' create myDataSet and myDataAdapter
    ' ...
    myDataAdapter.SelectCommand.Parameters.Add("@CategoryName", MySqlDbType.VarChar, 80).Value = "toasters"
    myDataAdapter.SelectCommand.Parameters.Add("@SerialNum", MySqlDbType.Long).Value = 239
    
    myDataAdapter.Fill(myDataSet)
End Sub 'AddSqlParameters 
  

C# example:

public void AddSqlParameters() 
{
// ...
// create myDataSet and myDataAdapter
// ...
  myDataAdapter.SelectCommand.Parameters.Add("@CategoryName", MySqlDbType.VarChar, 80).Value = "toasters";
  myDataAdapter.SelectCommand.Parameters.Add("@SerialNum", MySqlDbType.Long).Value = 239;
  myDataAdapter.Fill(myDataSet);
}
  

27.2.3.9. Using MySqlTransaction

Represents a SQL transaction to be made in a MySQL database. This class cannot be inherited.

The application creates a MySqlTransaction object by calling MySqlConnection.BeginTransaction on the MySqlConnection object. All subsequent operations associated with the transaction (for example, committing or aborting the transaction), are performed on the MySqlTransaction object.

Note

Once you have started a transaction on a connection all subsequent commands on that connection are applied within the scope of the transaction. You cannot execute an SQL statement on the same connection outside of the transaction scope. If you need to do this while executing statements that are part of a transaction, open a second a connection to be used for execution the non-transaction statements.

Examples

The following example creates a MySqlConnection and a MySqlTransaction. It also demonstrates how to use the MySqlConnection.BeginTransaction, MySqlTransaction.Commit, and MySqlTransaction.Rollback methods.

Visual Basic example:

Public Sub RunTransaction(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    
    Dim myCommand As MySqlCommand = myConnection.CreateCommand()
    Dim myTrans As MySqlTransaction
    
    ' Start a local transaction
    myTrans = myConnection.BeginTransaction()
    ' Must assign both transaction object and connection
    ' to Command object for a pending local transaction
    myCommand.Connection = myConnection
    myCommand.Transaction = myTrans
    
    Try
      myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')"
      myCommand.ExecuteNonQuery()
      myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')"
      myCommand.ExecuteNonQuery()
      myTrans.Commit()
      Console.WriteLine("Both records are written to database.")
    Catch e As Exception
      Try
        myTrans.Rollback()
      Catch ex As MySqlException
        If Not myTrans.Connection Is Nothing Then
          Console.WriteLine("An exception of type " & ex.GetType().ToString() & _
                            " was encountered while attempting to roll back the transaction.")
        End If
      End Try
    
      Console.WriteLine("An exception of type " & e.GetType().ToString() & _
                      "was encountered while inserting the data.")
      Console.WriteLine("Neither record was written to database.")
    Finally
      myConnection.Close()
    End Try
End Sub 'RunTransaction
  

C# example:

public void RunTransaction(string myConnString) 
 {
    MySqlConnection myConnection = new MySqlConnection(myConnString);
    myConnection.Open();
    MySqlCommand myCommand = myConnection.CreateCommand();
    MySqlTransaction myTrans;
    // Start a local transaction
    myTrans = myConnection.BeginTransaction();
    // Must assign both transaction object and connection
    // to Command object for a pending local transaction
    myCommand.Connection = myConnection;
    myCommand.Transaction = myTrans;
    try
    {
      myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
      myCommand.ExecuteNonQuery();
      myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
      myCommand.ExecuteNonQuery();
      myTrans.Commit();
      Console.WriteLine("Both records are written to database.");
    }
    catch(Exception e)
    {
      try
      {
        myTrans.Rollback();
      }
      catch (MySqlException ex)
      {
        if (myTrans.Connection != null)
        {
          Console.WriteLine("An exception of type " + ex.GetType() +
                            " was encountered while attempting to roll back the transaction.");
        }
      }
    
      Console.WriteLine("An exception of type " + e.GetType() +
                        " was encountered while inserting the data.");
      Console.WriteLine("Neither record was written to database.");
    }
    finally 
    {
      myConnection.Close();
    }
}
  
27.2.3.9.1. Rollback

Rolls back a transaction from a pending state.

The Rollback method is equivalent to the MySQL statement ROLLBACK. The transaction can only be rolled back from a pending state (after BeginTransaction has been called, but before Commit is called).

Examples

The following example creates MySqlConnection and a MySqlTransaction. It also demonstrates how to use the MySqlConnection.BeginTransaction, Commit, and Rollback methods.

Visual Basic example:

Public Sub RunSqlTransaction(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    
    Dim myCommand As MySqlCommand = myConnection.CreateCommand()
    Dim myTrans As MySqlTransaction
    
    ' Start a local transaction
    myTrans = myConnection.BeginTransaction()
    
    ' Must assign both transaction object and connection
    ' to Command object for a pending local transaction
    myCommand.Connection = myConnection
    myCommand.Transaction = myTrans
    
    Try
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (100, 'Description')"
      myCommand.ExecuteNonQuery()
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (101, 'Description')"
      myCommand.ExecuteNonQuery()
      myTrans.Commit()
      Console.WriteLine("Success.")
    Catch e As Exception
      Try
        myTrans.Rollback()
      Catch ex As MySqlException
        If Not myTrans.Connection Is Nothing Then
          Console.WriteLine("An exception of type " & ex.GetType().ToString() & _
                            " was encountered while attempting to roll back the transaction.")
        End If
      End Try
    
      Console.WriteLine("An exception of type " & e.GetType().ToString() & _
                      "was encountered while inserting the data.")
      Console.WriteLine("Neither record was written to database.")
    Finally
      myConnection.Close()
    End Try
End Sub

C# example:

public void RunSqlTransaction(string myConnString) 
 {
    MySqlConnection myConnection = new MySqlConnection(myConnString);
    myConnection.Open();
    MySqlCommand myCommand = myConnection.CreateCommand();
    MySqlTransaction myTrans;
    // Start a local transaction
    myTrans = myConnection.BeginTransaction();
    // Must assign both transaction object and connection
    // to Command object for a pending local transaction
    myCommand.Connection = myConnection;
    myCommand.Transaction = myTrans;
    try
    {
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (100, 'Description')";
      myCommand.ExecuteNonQuery();
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (101, 'Description')";
      myCommand.ExecuteNonQuery();
      myTrans.Commit();
      Console.WriteLine("Both records are written to database.");
    }
    catch(Exception e)
    {
      try
      {
        myTrans.Rollback();
      }
      catch (MySqlException ex)
      {
        if (myTrans.Connection != null)
        {
          Console.WriteLine("An exception of type " + ex.GetType() +
                            " was encountered while attempting to roll back the transaction.");
        }
      }
    
      Console.WriteLine("An exception of type " + e.GetType() +
                        " was encountered while inserting the data.");
      Console.WriteLine("Neither record was written to database.");
    }
    finally 
    {
      myConnection.Close();
    }
}  
27.2.3.9.2. Commit

Commits the database transaction.

The Commit method is equivalent to the MySQL SQL statement COMMIT.

Examples

The following example creates MySqlConnection and a MySqlTransaction. It also demonstrates how to use the MySqlConnection.BeginTransaction, Commit, and Rollback methods.

Visual Basic example:

Public Sub RunSqlTransaction(myConnString As String)
    Dim myConnection As New MySqlConnection(myConnString)
    myConnection.Open()
    
    Dim myCommand As MySqlCommand = myConnection.CreateCommand()
    Dim myTrans As MySqlTransaction
    
    ' Start a local transaction
    myTrans = myConnection.BeginTransaction()
    
    ' Must assign both transaction object and connection
    ' to Command object for a pending local transaction
    myCommand.Connection = myConnection
    myCommand.Transaction = myTrans
    
    Try
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (100, 'Description')"
      myCommand.ExecuteNonQuery()
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (101, 'Description')"
      myCommand.ExecuteNonQuery()
      myTrans.Commit()
      Console.WriteLine("Success.")
    Catch e As Exception
      Try
        myTrans.Rollback()
      Catch ex As MySqlException
        If Not myTrans.Connection Is Nothing Then
          Console.WriteLine("An exception of type " & ex.GetType().ToString() & _
                            " was encountered while attempting to roll back the transaction.")
        End If
      End Try
    
      Console.WriteLine("An exception of type " & e.GetType().ToString() & _
                      "was encountered while inserting the data.")
      Console.WriteLine("Neither record was written to database.")
    Finally
      myConnection.Close()
    End Try
End Sub

C# example:

public void RunSqlTransaction(string myConnString) 
 {
    MySqlConnection myConnection = new MySqlConnection(myConnString);
    myConnection.Open();
    MySqlCommand myCommand = myConnection.CreateCommand();
    MySqlTransaction myTrans;
    // Start a local transaction
    myTrans = myConnection.BeginTransaction();
    // Must assign both transaction object and connection
    // to Command object for a pending local transaction
    myCommand.Connection = myConnection;
    myCommand.Transaction = myTrans;
    try
    {
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (100, 'Description')";
      myCommand.ExecuteNonQuery();
      myCommand.CommandText = "Insert into mytable (id, desc) VALUES (101, 'Description')";
      myCommand.ExecuteNonQuery();
      myTrans.Commit();
      Console.WriteLine("Both records are written to database.");
    }
    catch(Exception e)
    {
      try
      {
        myTrans.Rollback();
      }
      catch (MySqlException ex)
      {
        if (myTrans.Connection != null)
        {
          Console.WriteLine("An exception of type " + ex.GetType() +
                            " was encountered while attempting to roll back the transaction.");
        }
      }
    
      Console.WriteLine("An exception of type " + e.GetType() +
                        " was encountered while inserting the data.");
      Console.WriteLine("Neither record was written to database.");
    }
    finally 
    {
      myConnection.Close();
    }
}  

27.2.4. Connector/NET Reference

This section of the manual contains a complete reference to the Connector/NET ADO.NET component, automatically generated from the embedded documentation.

27.2.4.1. MySql.Data.MySqlClient

Namespace hierarchy

Classes

ClassDescription
MySqlCommand 
MySqlCommandBuilder 
MySqlConnection 
MySqlDataAdapter 
MySqlDataReaderProvides a means of reading a forward-only stream of rows from a MySQL database. This class cannot be inherited.
MySqlErrorCollection of error codes that can be returned by the server
MySqlExceptionThe exception that is thrown when MySQL returns an error. This class cannot be inherited.
MySqlHelperHelper class that makes it easier to work with the provider.
MySqlInfoMessageEventArgsProvides data for the InfoMessage event. This class cannot be inherited.
MySqlParameterRepresents a parameter to a MySqlCommand , and optionally, its mapping to DataSetcolumns. This class cannot be inherited.
MySqlParameterCollectionRepresents a collection of parameters relevant to a MySqlCommand as well as their respective mappings to columns in a DataSet. This class cannot be inherited.
MySqlRowUpdatedEventArgsProvides data for the RowUpdated event. This class cannot be inherited.
MySqlRowUpdatingEventArgsProvides data for the RowUpdating event. This class cannot be inherited.
MySqlTransaction 

Delegates

DelegateDescription
MySqlInfoMessageEventHandlerRepresents the method that will handle the InfoMessage event of a MySqlConnection.
MySqlRowUpdatedEventHandlerRepresents the method that will handle the RowUpdatedevent of a MySqlDataAdapter .
MySqlRowUpdatingEventHandlerRepresents the method that will handle the RowUpdatingevent of a MySqlDataAdapter .

Enumerations

EnumerationDescription
MySqlDbTypeSpecifies MySQL specific data type of a field, property, for use in a MySqlParameter .
MySqlErrorCode 
27.2.4.1.1. MySql.Data.MySqlClientHierarchy

See Also

MySql.Data.MySqlClient Namespace

27.2.4.1.2. MySqlCommand Class

For a list of all members of this type, see MySqlCommand Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlCommand_
  Inherits Component_
  Implements IDbCommand, ICloneable

Syntax: C#

public sealed class MySqlCommand : Component, IDbCommand, ICloneable

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlCommand Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1. MySqlCommand Members

MySqlCommand overview

Public Instance Constructors

MySqlCommandOverloaded. Initializes a new instance of the MySqlCommand class.

Public Instance Properties

CommandText 
CommandTimeout 
CommandType 
Connection 
Container(inherited from Component)Gets the IContainerthat contains the Component.
IsPrepared 
Parameters 
Site(inherited from Component)Gets or sets the ISiteof the Component.
Transaction 
UpdatedRowSource 

Public Instance Methods

CancelAttempts to cancel the execution of a MySqlCommand. This operation is not supported.
CreateObjRef(inherited from MarshalByRefObject)Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.
CreateParameterCreates a new instance of a MySqlParameter object.
Dispose(inherited from Component)Releases all resources used by the Component.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
ExecuteNonQuery 
ExecuteReaderOverloaded.
ExecuteScalar 
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetLifetimeService(inherited from MarshalByRefObject)Retrieves the current lifetime service object that controls the lifetime policy for this instance.
GetType(inherited from Object)Gets the Typeof the current instance.
InitializeLifetimeService(inherited from MarshalByRefObject)Obtains a lifetime service object to control the lifetime policy for this instance.
Prepare 
ToString(inherited from Component)Returns a Stringcontaining the name of the Component, if any. This method should not be overridden.

Public Instance Events

Disposed(inherited from Component)Adds an event handler to listen to the Disposedevent on the component.

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1. MySqlCommand Constructor

Initializes a new instance of the MySqlCommand class.

Overload List

Initializes a new instance of the MySqlCommand class.

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.1. MySqlCommand Constructor ()

Initializes a new instance of the MySqlCommand class.

Syntax: Visual Basic

Overloads Public Sub New()

Syntax: C#

public MySqlCommand();

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace , MySqlCommand Constructor Overload List

27.2.4.1.2.1.1.2. MySqlCommand Constructor (String)

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal cmdText As String _
)

Syntax: C#

public MySqlCommand(
stringcmdText
);

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace , MySqlCommand Constructor Overload List

27.2.4.1.2.1.1.3. MySqlCommand Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal cmdText As String, _
   ByVal connection As MySqlConnection _
)

Syntax: C#

public MySqlCommand(
stringcmdText,
MySqlConnectionconnection
);

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace , MySqlCommand Constructor Overload List

27.2.4.1.2.1.1.3.1. MySqlConnection Class

For a list of all members of this type, see MySqlConnection Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlConnection_
  Inherits Component_
  Implements IDbConnection, ICloneable

Syntax: C#

public sealed class MySqlConnection : Component, IDbConnection, ICloneable

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlConnection Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1. MySqlConnection Members

MySqlConnection overview

Public Instance Constructors

MySqlConnectionOverloaded. Initializes a new instance of the MySqlConnection class.

Public Instance Properties

ConnectionString 
ConnectionTimeout 
Container(inherited from Component)Gets the IContainerthat contains the Component.
Database 
DataSourceGets the name of the MySQL server to which to connect.
ServerThreadReturns the id of the server thread this connection is executing on
ServerVersion 
Site(inherited from Component)Gets or sets the ISiteof the Component.
State 
UseCompressionIndicates if this connection should use compression when communicating with the server.

Public Instance Methods

BeginTransactionOverloaded.
ChangeDatabase 
Close 
CreateCommand 
CreateObjRef(inherited from MarshalByRefObject)Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.
Dispose(inherited from Component)Releases all resources used by the Component.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetLifetimeService(inherited from MarshalByRefObject)Retrieves the current lifetime service object that controls the lifetime policy for this instance.
GetType(inherited from Object)Gets the Typeof the current instance.
InitializeLifetimeService(inherited from MarshalByRefObject)Obtains a lifetime service object to control the lifetime policy for this instance.
Open 
PingPing
ToString(inherited from Component)Returns a Stringcontaining the name of the Component, if any. This method should not be overridden.

Public Instance Events

Disposed(inherited from Component)Adds an event handler to listen to the Disposedevent on the component.
InfoMessage 
StateChange 

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.1. MySqlConnection Constructor

Initializes a new instance of the MySqlConnection class.

Overload List

Initializes a new instance of the MySqlConnection class.

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.1.1. MySqlConnection Constructor

Initializes a new instance of the MySqlConnection class.

Syntax: Visual Basic

Overloads Public Sub New()

Syntax: C#

public MySqlConnection();

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace , MySqlConnection Constructor Overload List

27.2.4.1.2.1.1.3.1.1.1.2. MySqlConnection Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal connectionString As String _
)

Syntax: C#

public MySqlConnection(
stringconnectionString
);

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace , MySqlConnection Constructor Overload List

27.2.4.1.2.1.1.3.1.1.2. ConnectionString Property

Syntax: Visual Basic

NotOverridable Public Property ConnectionString As String _
_
  Implements IDbConnection.ConnectionString

Syntax: C#

public string ConnectionString {get; set;}

Implements

IDbConnection.ConnectionString

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.3. ConnectionTimeout Property

Syntax: Visual Basic

NotOverridable Public ReadOnly Property ConnectionTimeout As Integer _
_
  Implements IDbConnection.ConnectionTimeout

Syntax: C#

public int ConnectionTimeout {get;}

Implements

IDbConnection.ConnectionTimeout

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.4. Database Property

Syntax: Visual Basic

NotOverridable Public ReadOnly Property Database As String _
_
  Implements IDbConnection.Database

Syntax: C#

public string Database {get;}

Implements

IDbConnection.Database

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.5. DataSource Property

Gets the name of the MySQL server to which to connect.

Syntax: Visual Basic

Public ReadOnly Property DataSource As String

Syntax: C#

public string DataSource {get;}

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.6. ServerThread Property

Returns the id of the server thread this connection is executing on

Syntax: Visual Basic

Public ReadOnly Property ServerThread As Integer

Syntax: C#

public int ServerThread {get;}

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.7. ServerVersion Property

Syntax: Visual Basic

Public ReadOnly Property ServerVersion As String

Syntax: C#

public string ServerVersion {get;}

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.8. State Property

Syntax: Visual Basic

NotOverridable Public ReadOnly Property State As ConnectionState _
_
  Implements IDbConnection.State

Syntax: C#

public System.Data.ConnectionState State {get;}

Implements

IDbConnection.State

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.9. UseCompression Property

Indicates if this connection should use compression when communicating with the server.

Syntax: Visual Basic

Public ReadOnly Property UseCompression As Boolean

Syntax: C#

public bool UseCompression {get;}

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10. BeginTransaction Method

Overload List

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10.1. MySqlConnection.BeginTransaction Method

Syntax: Visual Basic

Overloads Public Function BeginTransaction() As MySqlTransaction

Syntax: C#

public MySqlTransaction BeginTransaction();

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace , MySqlConnection.BeginTransaction Overload List

27.2.4.1.2.1.1.3.1.1.10.1.1. MySqlTransaction Class

For a list of all members of this type, see MySqlTransaction Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlTransaction_
  Implements IDbTransaction, IDisposable

Syntax: C#

public sealed class MySqlTransaction : IDbTransaction, IDisposable

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlTransaction Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10.1.1.1. MySqlTransaction Members

MySqlTransaction overview

Public Instance Properties

ConnectionGets the MySqlConnection object associated with the transaction, or a null reference (Nothing in Visual Basic) if the transaction is no longer valid.
IsolationLevelSpecifies the IsolationLevelfor this transaction.

Public Instance Methods

Commit 
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
Rollback 
ToString(inherited from Object)Returns a Stringthat represents the current Object.

See Also

MySqlTransaction Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10.1.1.1.1. Connection Property

Gets the MySqlConnection object associated with the transaction, or a null reference (Nothing in Visual Basic) if the transaction is no longer valid.

Syntax: Visual Basic

Public ReadOnly Property Connection As MySqlConnection

Syntax: C#

public MySqlConnection Connection {get;}

Property Value

The MySqlConnection object associated with this transaction.

Remarks

A single application may have multiple database connections, each with zero or more transactions. This property enables you to determine the connection object associated with a particular transaction created by BeginTransaction .

See Also

MySqlTransaction Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10.1.1.1.2. IsolationLevel Property

Specifies the IsolationLevelfor this transaction.

Syntax: Visual Basic

NotOverridable Public ReadOnly Property IsolationLevel As IsolationLevel _
_
  Implements IDbTransaction.IsolationLevel

Syntax: C#

public System.Data.IsolationLevel IsolationLevel {get;}

Property Value

The IsolationLevel for this transaction. The default is ReadCommitted.

Implements

IDbTransaction.IsolationLevel

Remarks

Parallel transactions are not supported. Therefore, the IsolationLevel applies to the entire transaction.

See Also

MySqlTransaction Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10.1.1.1.3. MySqlTransaction.Commit Method

Syntax: Visual Basic

NotOverridable Public Sub Commit() _
_
  Implements IDbTransaction.Commit

Syntax: C#

public void Commit();

Implements

IDbTransaction.Commit

See Also

MySqlTransaction Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10.1.1.1.4. MySqlTransaction.Rollback Method

Syntax: Visual Basic

NotOverridable Public Sub Rollback() _
_
  Implements IDbTransaction.Rollback

Syntax: C#

public void Rollback();

Implements

IDbTransaction.Rollback

See Also

MySqlTransaction Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.10.2. MySqlConnection.BeginTransaction Method

Syntax: Visual Basic

Overloads Public Function BeginTransaction( _
   ByVal iso As IsolationLevel _
) As MySqlTransaction

Syntax: C#

public MySqlTransaction BeginTransaction(
IsolationLeveliso
);

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace , MySqlConnection.BeginTransaction Overload List

27.2.4.1.2.1.1.3.1.1.11. MySqlConnection.ChangeDatabase Method

Syntax: Visual Basic

NotOverridable Public Sub ChangeDatabase( _
   ByVal databaseName As String _
) _
_
  Implements IDbConnection.ChangeDatabase

Syntax: C#

public void ChangeDatabase(
stringdatabaseName
);

Implements

IDbConnection.ChangeDatabase

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.12. MySqlConnection.Close Method

Syntax: Visual Basic

NotOverridable Public Sub Close() _
_
  Implements IDbConnection.Close

Syntax: C#

public void Close();

Implements

IDbConnection.Close

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.13. MySqlConnection.CreateCommand Method

Syntax: Visual Basic

Public Function CreateCommand() As MySqlCommand

Syntax: C#

public MySqlCommand CreateCommand();

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.14. MySqlConnection.Open Method

Syntax: Visual Basic

NotOverridable Public Sub Open() _
_
  Implements IDbConnection.Open

Syntax: C#

public void Open();

Implements

IDbConnection.Open

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.15. MySqlConnection.Ping Method

Ping

Syntax: Visual Basic

Public Function Ping() As Boolean

Syntax: C#

public bool Ping();

Return Value

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16. MySqlConnection.InfoMessage Event

Syntax: Visual Basic

Public Event InfoMessage As MySqlInfoMessageEventHandler

Syntax: C#

public event MySqlInfoMessageEventHandler InfoMessage;

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1. MySqlInfoMessageEventHandler Delegate

Represents the method that will handle the InfoMessage event of a MySqlConnection .

Syntax: Visual Basic

Public Delegate Sub MySqlInfoMessageEventHandler( _
   ByVal sender As Object, _
   ByVal args As MySqlInfoMessageEventArgs _
)

Syntax: C#

public delegate void MySqlInfoMessageEventHandler(
objectsender,
MySqlInfoMessageEventArgsargs
);

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1. MySqlInfoMessageEventArgs Class

Provides data for the InfoMessage event. This class cannot be inherited.

For a list of all members of this type, see MySqlInfoMessageEventArgs Members .

Syntax: Visual Basic

Public Class MySqlInfoMessageEventArgs_
  Inherits EventArgs

Syntax: C#

public class MySqlInfoMessageEventArgs : EventArgs

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlInfoMessageEventArgs Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1. MySqlInfoMessageEventArgs Members

MySqlInfoMessageEventArgs overview

Public Instance Constructors

Public Instance Fields

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
ToString(inherited from Object)Returns a Stringthat represents the current Object.

Protected Instance Methods

Finalize(inherited from Object)Allows an Objectto attempt to free resources and perform other cleanup operations before the Objectis reclaimed by garbage collection.
MemberwiseClone(inherited from Object)Creates a shallow copy of the current Object.

See Also

MySqlInfoMessageEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.1. MySqlInfoMessageEventArgs Constructor

Initializes a new instance of the MySqlInfoMessageEventArgs class.

Syntax: Visual Basic

Public Sub New()

Syntax: C#

public MySqlInfoMessageEventArgs();

See Also

MySqlInfoMessageEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.2. MySqlInfoMessageEventArgs.errors Field

Syntax: Visual Basic

Public errors As MySqlError()

Syntax: C#

public MySqlError[] errors;

See Also

MySqlInfoMessageEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.2.1. MySqlError Class

Collection of error codes that can be returned by the server

For a list of all members of this type, see MySqlError Members .

Syntax: Visual Basic

Public Class MySqlError

Syntax: C#

public class MySqlError

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlError Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.2.1.1. MySqlError Members

MySqlError overview

Public Instance Constructors

Public Instance Properties

CodeError code
LevelError level
MessageError message

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
ToString(inherited from Object)Returns a Stringthat represents the current Object.

Protected Instance Methods

Finalize(inherited from Object)Allows an Objectto attempt to free resources and perform other cleanup operations before the Objectis reclaimed by garbage collection.
MemberwiseClone(inherited from Object)Creates a shallow copy of the current Object.

See Also

MySqlError Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.2.1.1.1. MySqlError Constructor

Syntax: Visual Basic

Public Sub New( _
   ByVal level As String, _
   ByVal code As Integer, _
   ByVal message As String _
)

Syntax: C#

public MySqlError(
stringlevel,
intcode,
stringmessage
);

Parameters

  • level:

  • code:

  • message:

See Also

MySqlError Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.2.1.1.2. Code Property

Error code

Syntax: Visual Basic

Public ReadOnly Property Code As Integer

Syntax: C#

public int Code {get;}

See Also

MySqlError Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.2.1.1.3. Level Property

Error level

Syntax: Visual Basic

Public ReadOnly Property Level As String

Syntax: C#

public string Level {get;}

See Also

MySqlError Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.16.1.1.1.2.1.1.4. Message Property

Error message

Syntax: Visual Basic

Public ReadOnly Property Message As String

Syntax: C#

public string Message {get;}

See Also

MySqlError Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.3.1.1.17. MySqlConnection.StateChange Event

Syntax: Visual Basic

Public Event StateChange As StateChangeEventHandler

Syntax: C#

public event StateChangeEventHandler StateChange;

See Also

MySqlConnection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.1.4. MySqlCommand Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal cmdText As String, _
   ByVal connection As MySqlConnection, _
   ByVal transaction As MySqlTransaction _
)

Syntax: C#

public MySqlCommand(
stringcmdText,
MySqlConnectionconnection,
MySqlTransactiontransaction
);

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace , MySqlCommand Constructor Overload List

27.2.4.1.2.1.2. CommandText Property

Syntax: Visual Basic

NotOverridable Public Property CommandText As String _
_
  Implements IDbCommand.CommandText

Syntax: C#

public string CommandText {get; set;}

Implements

IDbCommand.CommandText

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.3. CommandTimeout Property

Syntax: Visual Basic

NotOverridable Public Property CommandTimeout As Integer _
_
  Implements IDbCommand.CommandTimeout

Syntax: C#

public int CommandTimeout {get; set;}

Implements

IDbCommand.CommandTimeout

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.4. CommandType Property

Syntax: Visual Basic

NotOverridable Public Property CommandType As CommandType _
_
  Implements IDbCommand.CommandType

Syntax: C#

public System.Data.CommandType CommandType {get; set;}

Implements

IDbCommand.CommandType

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.5. Connection Property

Syntax: Visual Basic

Public Property Connection As MySqlConnection

Syntax: C#

public MySqlConnection Connection {get; set;}

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.6. IsPrepared Property

Syntax: Visual Basic

Public ReadOnly Property IsPrepared As Boolean

Syntax: C#

public bool IsPrepared {get;}

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7. Parameters Property

Syntax: Visual Basic

Public ReadOnly Property Parameters As MySqlParameterCollection

Syntax: C#

public MySqlParameterCollection Parameters {get;}

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1. MySqlParameterCollection Class

Represents a collection of parameters relevant to a MySqlCommand as well as their respective mappings to columns in a DataSet. This class cannot be inherited.

For a list of all members of this type, see MySqlParameterCollection Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlParameterCollection_
  Inherits MarshalByRefObject_
  Implements IDataParameterCollection, IList, ICollection, IEnumerable

Syntax: C#

public sealed class MySqlParameterCollection : MarshalByRefObject, IDataParameterCollection, IList, ICollection, IEnumerable

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlParameterCollection Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1. MySqlParameterCollection Members

MySqlParameterCollection overview

Public Instance Constructors

MySqlParameterCollection ConstructorInitializes a new instance of the MySqlParameterCollection class.

Public Instance Properties

CountGets the number of MySqlParameter objects in the collection.
ItemOverloaded. Gets the MySqlParameter with a specified attribute. In C#, this property is the indexer for the MySqlParameterCollection class.

Public Instance Methods

AddOverloaded. Adds the specified MySqlParameter object to the MySqlParameterCollection .
ClearRemoves all items from the collection.
ContainsOverloaded. Gets a value indicating whether a MySqlParameter exists in the collection.
CopyToCopies MySqlParameter objects from the MySqlParameterCollection to the specified array.
CreateObjRef(inherited from MarshalByRefObject)Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetLifetimeService(inherited from MarshalByRefObject)Retrieves the current lifetime service object that controls the lifetime policy for this instance.
GetType(inherited from Object)Gets the Typeof the current instance.
IndexOfOverloaded. Gets the location of a MySqlParameter in the collection.
InitializeLifetimeService(inherited from MarshalByRefObject)Obtains a lifetime service object to control the lifetime policy for this instance.
InsertInserts a MySqlParameter into the collection at the specified index.
RemoveRemoves the specified MySqlParameter from the collection.
RemoveAtOverloaded. Removes the specified MySqlParameter from the collection.
ToString(inherited from Object)Returns a Stringthat represents the current Object.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.1. MySqlParameterCollection Constructor

Initializes a new instance of the MySqlParameterCollection class.

Syntax: Visual Basic

Public Sub New()

Syntax: C#

public MySqlParameterCollection();

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.2. Count Property

Gets the number of MySqlParameter objects in the collection.

Syntax: Visual Basic

NotOverridable Public ReadOnly Property Count As Integer _
_
  Implements ICollection.Count

Syntax: C#

public int Count {get;}

Implements

ICollection.Count

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3. Item Property

Gets the MySqlParameter with a specified attribute. In C#, this property is the indexer for the MySqlParameterCollection class.

Overload List

Gets the MySqlParameter at the specified index.

Gets the MySqlParameter with the specified name.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1. MySqlParameter Class

Represents a parameter to a MySqlCommand , and optionally, its mapping to DataSetcolumns. This class cannot be inherited.

For a list of all members of this type, see MySqlParameter Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlParameter_
  Inherits MarshalByRefObject_
  Implements IDataParameter, IDbDataParameter, ICloneable

Syntax: C#

public sealed class MySqlParameter : MarshalByRefObject, IDataParameter, IDbDataParameter, ICloneable

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlParameter Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1. MySqlParameter Members

MySqlParameter overview

Public Instance Constructors

MySqlParameterOverloaded. Initializes a new instance of the MySqlParameter class.

Public Instance Properties

DbTypeGets or sets the DbTypeof the parameter.
DirectionGets or sets a value indicating whether the parameter is input-only, output-only, bidirectional, or a stored procedure return value parameter. As of MySQL version 4.1 and earlier, input-only is the only valid choice.
IsNullableGets or sets a value indicating whether the parameter accepts null values.
IsUnsigned 
MySqlDbTypeGets or sets the MySqlDbType of the parameter.
ParameterNameGets or sets the name of the MySqlParameter.
PrecisionGets or sets the maximum number of digits used to represent the Value property.
ScaleGets or sets the number of decimal places to which Value is resolved.
SizeGets or sets the maximum size, in bytes, of the data within the column.
SourceColumnGets or sets the name of the source column that is mapped to the DataSetand used for loading or returning the Value .
SourceVersionGets or sets the DataRowVersionto use when loading Value .
ValueGets or sets the value of the parameter.

Public Instance Methods

CreateObjRef(inherited from MarshalByRefObject)Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetLifetimeService(inherited from MarshalByRefObject)Retrieves the current lifetime service object that controls the lifetime policy for this instance.
GetType(inherited from Object)Gets the Typeof the current instance.
InitializeLifetimeService(inherited from MarshalByRefObject)Obtains a lifetime service object to control the lifetime policy for this instance.
ToStringOverridden. Gets a string containing the ParameterName .

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.1. MySqlParameter Constructor

Initializes a new instance of the MySqlParameter class.

Overload List

Initializes a new instance of the MySqlParameter class.

Initializes a new instance of the MySqlParameter class with the parameter name and the data type.

Initializes a new instance of the MySqlParameter class with the parameter name, the MySqlDbType , and the size.

Initializes a new instance of the MySqlParameter class with the parameter name, the type of the parameter, the size of the parameter, a ParameterDirection, the precision of the parameter, the scale of the parameter, the source column, a DataRowVersionto use, and the value of the parameter.

Initializes a new instance of the MySqlParameter class with the parameter name, the MySqlDbType , the size, and the source column name.

Initializes a new instance of the MySqlParameter class with the parameter name and a value of the new MySqlParameter.

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.1.1. MySqlParameter Constructor ()

Initializes a new instance of the MySqlParameter class.

Syntax: Visual Basic

Overloads Public Sub New()

Syntax: C#

public MySqlParameter();

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace , MySqlParameter Constructor Overload List

27.2.4.1.2.1.7.1.1.3.1.1.1.2. MySqlParameter Constructor

Initializes a new instance of the MySqlParameter class with the parameter name and the data type.

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal parameterName As String, _
   ByVal dbType As MySqlDbType _
)

Syntax: C#

public MySqlParameter(
stringparameterName,
MySqlDbTypedbType
);

Parameters

  • parameterName: The name of the parameter to map.

  • dbType: One of the MySqlDbType values.

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace , MySqlParameter Constructor Overload List

27.2.4.1.2.1.7.1.1.3.1.1.1.2.1. MySqlDbType Enumeration

Specifies MySQL specific data type of a field, property, for use in a MySqlParameter .

Syntax: Visual Basic

Public Enum MySqlDbType

Syntax: C#

public enum MySqlDbType

Members

Member NameDescription
NewdateObsolete. Use Datetime or Date type.
TimestampA timestamp. The range is '1970-01-01 00:00:01' to sometime in the year 2038.
Time

The range is '-838:59:59' to '838:59:59'

DateDate The supported range is '1000-01-01' to '9999-12-31'
DatetimeThe supported range is '1000-01-01 00:00:00' to '9999-12-31 23:59:59'
YearA year in 2- or 4-digit format (default is 4-digit). The allowable values are 1901 to 2155, 0000 in the 4-digit year format, and 1970-2069 if you use the 2-digit format (70-69).
TinyBlobA BLOB column with a maximum length of 255 (2^8 - 1) characters
BlobA BLOB column with a maximum length of 65535 (2^16 - 1) characters
MediumBlobA BLOB column with a maximum length of 16777215 (2^24 - 1) characters
LongBlobA BLOB column with a maximum length of 4294967295 or 4G (2^32 - 1) characters
Int16

A 16-bit signed integer. The signed range is -32768 to 32767. The unsigned range is 0 to 65535

Int24Specifies a 24 (3 byte) signed or unsigned value
Int32

A 32-bit signed integer

Int64

A 64-bit signed integer

Byte

The signed range is -128 to 127. The unsigned range is 0 to 255.

Float

A small (single-precision) floating-point number. Allowable values are -3.402823466E+38 to -1.175494351E-38, 0, and 1.175494351E-38 to 3.402823466E+38.

Double

A normal-size (double-precision) floating-point number. Allowable values are -1.7976931348623157E+308 to -2.2250738585072014E-308, 0, and 2.2250738585072014E-308 to 1.7976931348623157E+308.

UByteAn 8-bit unsigned value
UInt16A 16-bit unsigned value
UInt24A 24-bit unsigned value
UInt32A 32-bit unsigned value
UInt64A 64-bit unsigned value
Decimal

A fixed precision and scale numeric value between -1038 -1 and 10 38 -1

NewDecimalNew Decimal
SetA set. A string object that can have zero or more values, each of which must be chosen from the list of values 'value1', 'value2', ... A SET can have a maximum of 64 members.
StringObsolete Use VarChar type
VarCharA variable-length string containing 0 to 255 characters
VarStringA variable-length string containing 0 to 65535 characters
EnumAn enumeration. A string object that can have only one value, chosen from the list of values 'value1', 'value2', ..., NULL or the special "" error value. An ENUM can have a maximum of 65535 distinct values.
Geometry 
BitBit-field data type
TinyTextA nonbinary string column supporting a maximum length of 255 (2^8 - 1) characters
TextA nonbinary string column supporting a maximum length of 65535 (2^16 - 1) characters
MediumTextA nonbinary string column supporting a maximum length of 16777215 (2^24 - 1) characters
LongTextA nonbinary string column supporting a maximum length of 4294967295 (2^32 - 1) characters

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.1.3. MySqlParameter Constructor (String, MySqlDbType, Int32)

Initializes a new instance of the MySqlParameter class with the parameter name, the MySqlDbType , and the size.

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal parameterName As String, _
   ByVal dbType As MySqlDbType, _
   ByVal size As Integer _
)

Syntax: C#

public MySqlParameter(
stringparameterName,
MySqlDbTypedbType,
intsize
);

Parameters

  • parameterName: The name of the parameter to map.

  • dbType: One of the MySqlDbType values.

  • size: The length of the parameter.

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace , MySqlParameter Constructor Overload List

27.2.4.1.2.1.7.1.1.3.1.1.1.4. MySqlParameter Constructor

Initializes a new instance of the MySqlParameter class with the parameter name, the type of the parameter, the size of the parameter, a ParameterDirection, the precision of the parameter, the scale of the parameter, the source column, a DataRowVersionto use, and the value of the parameter.

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal parameterName As String, _
   ByVal dbType As MySqlDbType, _
   ByVal size As Integer, _
   ByVal direction As ParameterDirection, _
   ByVal isNullable As Boolean, _
   ByVal precision As Byte, _
   ByVal scale As Byte, _
   ByVal sourceColumn As String, _
   ByVal sourceVersion As DataRowVersion, _
   ByVal value As Object _
)

Syntax: C#

public MySqlParameter(
stringparameterName,
MySqlDbTypedbType,
intsize,
ParameterDirectiondirection,
boolisNullable,
byteprecision,
bytescale,
stringsourceColumn,
DataRowVersionsourceVersion,
objectvalue
);

Parameters

  • parameterName: The name of the parameter to map.

  • dbType: One of the MySqlDbType values.

  • size: The length of the parameter.

  • direction: One of the ParameterDirectionvalues.

  • isNullable: true if the value of the field can be null, otherwise false.

  • precision: The total number of digits to the left and right of the decimal point to which Value is resolved.

  • scale: The total number of decimal places to which Value is resolved.

  • sourceColumn: The name of the source column.

  • sourceVersion: One of the DataRowVersionvalues.

  • value: An Objectthat is the value of the MySqlParameter .

Exceptions

Exception TypeCondition
ArgumentException 

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace , MySqlParameter Constructor Overload List

27.2.4.1.2.1.7.1.1.3.1.1.1.4.1. Value Property

Gets or sets the value of the parameter.

Syntax: Visual Basic

NotOverridable Public Property Value As Object _
_
  Implements IDataParameter.Value

Syntax: C#

public object Value {get; set;}

Implements

IDataParameter.Value

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.1.5. MySqlParameter Constructor

Initializes a new instance of the MySqlParameter class with the parameter name, the MySqlDbType , the size, and the source column name.

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal parameterName As String, _
   ByVal dbType As MySqlDbType, _
   ByVal size As Integer, _
   ByVal sourceColumn As String _
)

Syntax: C#

public MySqlParameter(
stringparameterName,
MySqlDbTypedbType,
intsize,
stringsourceColumn
);

Parameters

  • parameterName: The name of the parameter to map.

  • dbType: One of the MySqlDbType values.

  • size: The length of the parameter.

  • sourceColumn: The name of the source column.

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace , MySqlParameter Constructor Overload List

27.2.4.1.2.1.7.1.1.3.1.1.1.6. MySqlParameter Constructor

Initializes a new instance of the MySqlParameter class with the parameter name and a value of the new MySqlParameter.

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal parameterName As String, _
   ByVal value As Object _
)

Syntax: C#

public MySqlParameter(
stringparameterName,
objectvalue
);

Parameters

  • parameterName: The name of the parameter to map.

  • value: An Objectthat is the value of the MySqlParameter .

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace , MySqlParameter Constructor Overload List

27.2.4.1.2.1.7.1.1.3.1.1.2. DbType Property

Gets or sets the DbTypeof the parameter.

Syntax: Visual Basic

NotOverridable Public Property DbType As DbType _
_
  Implements IDataParameter.DbType

Syntax: C#

public System.Data.DbType DbType {get; set;}

Implements

IDataParameter.DbType

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.3. Direction Property

Gets or sets a value indicating whether the parameter is input-only, output-only, bidirectional, or a stored procedure return value parameter. As of MySQL version 4.1 and earlier, input-only is the only valid choice.

Syntax: Visual Basic

NotOverridable Public Property Direction As ParameterDirection _
_
  Implements IDataParameter.Direction

Syntax: C#

public System.Data.ParameterDirection Direction {get; set;}

Implements

IDataParameter.Direction

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.4. IsNullable Property

Gets or sets a value indicating whether the parameter accepts null values.

Syntax: Visual Basic

NotOverridable Public Property IsNullable As Boolean _
_
  Implements IDataParameter.IsNullable

Syntax: C#

public bool IsNullable {get; set;}

Implements

IDataParameter.IsNullable

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.5. IsUnsigned Property

Syntax: Visual Basic

Public Property IsUnsigned As Boolean

Syntax: C#

public bool IsUnsigned {get; set;}

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.6. MySqlDbType Property

Gets or sets the MySqlDbType of the parameter.

Syntax: Visual Basic

Public Property MySqlDbType As MySqlDbType

Syntax: C#

public MySqlDbType MySqlDbType {get; set;}

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.7. ParameterName Property

Gets or sets the name of the MySqlParameter.

Syntax: Visual Basic

NotOverridable Public Property ParameterName As String _
_
  Implements IDataParameter.ParameterName

Syntax: C#

public string ParameterName {get; set;}

Implements

IDataParameter.ParameterName

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.8. Precision Property

Gets or sets the maximum number of digits used to represent the Value property.

Syntax: Visual Basic

NotOverridable Public Property Precision As Byte _
_
  Implements IDbDataParameter.Precision

Syntax: C#

public byte Precision {get; set;}

Implements

IDbDataParameter.Precision

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.9. Scale Property

Gets or sets the number of decimal places to which Value is resolved.

Syntax: Visual Basic

NotOverridable Public Property Scale As Byte _
_
  Implements IDbDataParameter.Scale

Syntax: C#

public byte Scale {get; set;}

Implements

IDbDataParameter.Scale

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.10. Size Property

Gets or sets the maximum size, in bytes, of the data within the column.

Syntax: Visual Basic

NotOverridable Public Property Size As Integer _
_
  Implements IDbDataParameter.Size

Syntax: C#

public int Size {get; set;}

Implements

IDbDataParameter.Size

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.11. SourceColumn Property

Gets or sets the name of the source column that is mapped to the DataSetand used for loading or returning the Value .

Syntax: Visual Basic

NotOverridable Public Property SourceColumn As String _
_
  Implements IDataParameter.SourceColumn

Syntax: C#

public string SourceColumn {get; set;}

Implements

IDataParameter.SourceColumn

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.12. SourceVersion Property

Gets or sets the DataRowVersionto use when loading Value .

Syntax: Visual Basic

NotOverridable Public Property SourceVersion As DataRowVersion _
_
  Implements IDataParameter.SourceVersion

Syntax: C#

public System.Data.DataRowVersion SourceVersion {get; set;}

Implements

IDataParameter.SourceVersion

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.1.1.13. MySqlParameter.ToString Method

Overridden. Gets a string containing the ParameterName .

Syntax: Visual Basic

Overrides Public Function ToString() As String

Syntax: C#

public override string ToString();

Return Value

See Also

MySqlParameter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.3.2. Item Property (Int32)

Gets the MySqlParameter at the specified index.

Syntax: Visual Basic

Overloads Public Default Property Item( _
   ByVal index As Integer _
) As MySqlParameter

Syntax: C#

public MySqlParameter this[
intindex
] {get; set;}

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Item Overload List

27.2.4.1.2.1.7.1.1.3.3. Item Property (String)

Gets the MySqlParameter with the specified name.

Syntax: Visual Basic

Overloads Public Default Property Item( _
   ByVal name As String _
) As MySqlParameter

Syntax: C#

public MySqlParameter this[
stringname
] {get; set;}

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Item Overload List

27.2.4.1.2.1.7.1.1.4. Add Method

Adds the specified MySqlParameter object to the MySqlParameterCollection .

Overload List

Adds the specified MySqlParameter object to the MySqlParameterCollection .

Adds the specified MySqlParameter object to the MySqlParameterCollection .

Adds a MySqlParameter to the MySqlParameterCollection given the parameter name and the data type.

Adds a MySqlParameter to the MySqlParameterCollection with the parameter name, the data type, and the column length.

Adds a MySqlParameter to the MySqlParameterCollection with the parameter name, the data type, the column length, and the source column name.

Adds a MySqlParameter to the MySqlParameterCollection given the specified parameter name and value.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.4.1. MySqlParameterCollection.Add Method

Adds the specified MySqlParameter object to the MySqlParameterCollection .

Syntax: Visual Basic

Overloads Public Function Add( _
   ByVal value As MySqlParameter _
) As MySqlParameter

Syntax: C#

public MySqlParameter Add(
MySqlParametervalue
);

Parameters

Return Value

The newly added MySqlParameter object.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Add Overload List

27.2.4.1.2.1.7.1.1.4.2. MySqlParameterCollection.Add Method

Adds the specified MySqlParameter object to the MySqlParameterCollection .

Syntax: Visual Basic

NotOverridable Overloads Public Function Add( _
   ByVal value As Object _
) As Integer _
_
  Implements IList.Add

Syntax: C#

public int Add(
objectvalue
);

Parameters

Return Value

The index of the new MySqlParameter object.

Implements

IList.Add

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Add Overload List

27.2.4.1.2.1.7.1.1.4.3. MySqlParameterCollection.Add Method

Adds a MySqlParameter to the MySqlParameterCollection given the parameter name and the data type.

Syntax: Visual Basic

Overloads Public Function Add( _
   ByVal parameterName As String, _
   ByVal dbType As MySqlDbType _
) As MySqlParameter

Syntax: C#

public MySqlParameter Add(
stringparameterName,
MySqlDbTypedbType
);

Parameters

  • parameterName: The name of the parameter.

  • dbType: One of the MySqlDbType values.

Return Value

The newly added MySqlParameter object.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Add Overload List

27.2.4.1.2.1.7.1.1.4.4. MySqlParameterCollection.Add Method

Adds a MySqlParameter to the MySqlParameterCollection with the parameter name, the data type, and the column length.

Syntax: Visual Basic

Overloads Public Function Add( _
   ByVal parameterName As String, _
   ByVal dbType As MySqlDbType, _
   ByVal size As Integer _
) As MySqlParameter

Syntax: C#

public MySqlParameter Add(
stringparameterName,
MySqlDbTypedbType,
intsize
);

Parameters

  • parameterName: The name of the parameter.

  • dbType: One of the MySqlDbType values.

  • size: The length of the column.

Return Value

The newly added MySqlParameter object.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Add Overload List

27.2.4.1.2.1.7.1.1.4.5. MySqlParameterCollection.Add Method

Adds a MySqlParameter to the MySqlParameterCollection with the parameter name, the data type, the column length, and the source column name.

Syntax: Visual Basic

Overloads Public Function Add( _
   ByVal parameterName As String, _
   ByVal dbType As MySqlDbType, _
   ByVal size As Integer, _
   ByVal sourceColumn As String _
) As MySqlParameter

Syntax: C#

public MySqlParameter Add(
stringparameterName,
MySqlDbTypedbType,
intsize,
stringsourceColumn
);

Parameters

  • parameterName: The name of the parameter.

  • dbType: One of the MySqlDbType values.

  • size: The length of the column.

  • sourceColumn: The name of the source column.

Return Value

The newly added MySqlParameter object.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Add Overload List

27.2.4.1.2.1.7.1.1.4.6. MySqlParameterCollection.Add Method

Adds a MySqlParameter to the MySqlParameterCollection given the specified parameter name and value.

Syntax: Visual Basic

Overloads Public Function Add( _
   ByVal parameterName As String, _
   ByVal value As Object _
) As MySqlParameter

Syntax: C#

public MySqlParameter Add(
stringparameterName,
objectvalue
);

Parameters

  • parameterName: The name of the parameter.

  • value: The Value of the MySqlParameter to add to the collection.

Return Value

The newly added MySqlParameter object.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Add Overload List

27.2.4.1.2.1.7.1.1.5. MySqlParameterCollection.Clear Method

Removes all items from the collection.

Syntax: Visual Basic

NotOverridable Public Sub Clear() _
_
  Implements IList.Clear

Syntax: C#

public void Clear();

Implements

IList.Clear

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.6. Contains Method

Gets a value indicating whether a MySqlParameter exists in the collection.

Overload List

Gets a value indicating whether a MySqlParameter exists in the collection.

Gets a value indicating whether a MySqlParameter with the specified parameter name exists in the collection.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.6.1. MySqlParameterCollection.Contains Method

Gets a value indicating whether a MySqlParameter exists in the collection.

Syntax: Visual Basic

NotOverridable Overloads Public Function Contains( _
   ByVal value As Object _
) As Boolean _
_
  Implements IList.Contains

Syntax: C#

public bool Contains(
objectvalue
);

Parameters

Return Value

true if the collection contains the MySqlParameter object; otherwise, false.

Implements

IList.Contains

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Contains Overload List

27.2.4.1.2.1.7.1.1.6.2. MySqlParameterCollection.Contains Method

Gets a value indicating whether a MySqlParameter with the specified parameter name exists in the collection.

Syntax: Visual Basic

NotOverridable Overloads Public Function Contains( _
   ByVal name As String _
) As Boolean _
_
  Implements IDataParameterCollection.Contains

Syntax: C#

public bool Contains(
stringname
);

Parameters

Return Value

true if the collection contains the parameter; otherwise, false.

Implements

IDataParameterCollection.Contains

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.Contains Overload List

27.2.4.1.2.1.7.1.1.7. MySqlParameterCollection.CopyTo Method

Copies MySqlParameter objects from the MySqlParameterCollection to the specified array.

Syntax: Visual Basic

NotOverridable Public Sub CopyTo( _
   ByVal array As Array, _
   ByVal index As Integer _
) _
_
  Implements ICollection.CopyTo

Syntax: C#

public void CopyTo(
Arrayarray,
intindex
);

Parameters

  • array:

  • index:

Implements

ICollection.CopyTo

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.8. IndexOf Method

Gets the location of a MySqlParameter in the collection.

Overload List

Gets the location of a MySqlParameter in the collection.

Gets the location of the MySqlParameter in the collection with a specific parameter name.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.8.1. MySqlParameterCollection.IndexOf Method

Gets the location of a MySqlParameter in the collection.

Syntax: Visual Basic

NotOverridable Overloads Public Function IndexOf( _
   ByVal value As Object _
) As Integer _
_
  Implements IList.IndexOf

Syntax: C#

public int IndexOf(
objectvalue
);

Parameters

Return Value

The zero-based location of the MySqlParameter in the collection.

Implements

IList.IndexOf

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.IndexOf Overload List

27.2.4.1.2.1.7.1.1.8.2. MySqlParameterCollection.IndexOf Method

Gets the location of the MySqlParameter in the collection with a specific parameter name.

Syntax: Visual Basic

NotOverridable Overloads Public Function IndexOf( _
   ByVal parameterName As String _
) As Integer _
_
  Implements IDataParameterCollection.IndexOf

Syntax: C#

public int IndexOf(
stringparameterName
);

Parameters

Return Value

The zero-based location of the MySqlParameter in the collection.

Implements

IDataParameterCollection.IndexOf

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.IndexOf Overload List

27.2.4.1.2.1.7.1.1.9. MySqlParameterCollection.Insert Method

Inserts a MySqlParameter into the collection at the specified index.

Syntax: Visual Basic

NotOverridable Public Sub Insert( _
   ByVal index As Integer, _
   ByVal value As Object _
) _
_
  Implements IList.Insert

Syntax: C#

public void Insert(
intindex,
objectvalue
);

Parameters

  • index:

  • value:

Implements

IList.Insert

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.10. MySqlParameterCollection.Remove Method

Removes the specified MySqlParameter from the collection.

Syntax: Visual Basic

NotOverridable Public Sub Remove( _
   ByVal value As Object _
) _
_
  Implements IList.Remove

Syntax: C#

public void Remove(
objectvalue
);

Parameters

  • value:

Implements

IList.Remove

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.11. RemoveAt Method

Removes the specified MySqlParameter from the collection.

Overload List

Removes the specified MySqlParameter from the collection using a specific index.

Removes the specified MySqlParameter from the collection using the parameter name.

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.7.1.1.11.1. MySqlParameterCollection.RemoveAt Method

Removes the specified MySqlParameter from the collection using a specific index.

Syntax: Visual Basic

NotOverridable Overloads Public Sub RemoveAt( _
   ByVal index As Integer _
) _
_
  Implements IList.RemoveAt

Syntax: C#

public void RemoveAt(
intindex
);

Parameters

  • index: The zero-based index of the parameter.

Implements

IList.RemoveAt

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.RemoveAt Overload List

27.2.4.1.2.1.7.1.1.11.2. MySqlParameterCollection.RemoveAt Method

Removes the specified MySqlParameter from the collection using the parameter name.

Syntax: Visual Basic

NotOverridable Overloads Public Sub RemoveAt( _
   ByVal name As String _
) _
_
  Implements IDataParameterCollection.RemoveAt

Syntax: C#

public void RemoveAt(
stringname
);

Parameters

Implements

IDataParameterCollection.RemoveAt

See Also

MySqlParameterCollection Class , MySql.Data.MySqlClient Namespace , MySqlParameterCollection.RemoveAt Overload List

27.2.4.1.2.1.8. Transaction Property

Syntax: Visual Basic

Public Property Transaction As MySqlTransaction

Syntax: C#

public MySqlTransaction Transaction {get; set;}

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.9. UpdatedRowSource Property

Syntax: Visual Basic

NotOverridable Public Property UpdatedRowSource As UpdateRowSource _
_
  Implements IDbCommand.UpdatedRowSource

Syntax: C#

public System.Data.UpdateRowSource UpdatedRowSource {get; set;}

Implements

IDbCommand.UpdatedRowSource

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.10. MySqlCommand.Cancel Method

Attempts to cancel the execution of a MySqlCommand. This operation is not supported.

Syntax: Visual Basic

NotOverridable Public Sub Cancel() _
_
  Implements IDbCommand.Cancel

Syntax: C#

public void Cancel();

Implements

IDbCommand.Cancel

Remarks

Cancelling an executing command is currently not supported on any version of MySQL.

Exceptions

Exception TypeCondition
NotSupportedExceptionThis operation is not supported.

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.11. MySqlCommand.CreateParameter Method

Creates a new instance of a MySqlParameter object.

Syntax: Visual Basic

Public Function CreateParameter() As MySqlParameter

Syntax: C#

public MySqlParameter CreateParameter();

Return Value

A MySqlParameter object.

Remarks

This method is a strongly-typed version of CreateParameter.

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.12. MySqlCommand.ExecuteNonQuery Method

Syntax: Visual Basic

NotOverridable Public Function ExecuteNonQuery() As Integer _
_
  Implements IDbCommand.ExecuteNonQuery

Syntax: C#

public int ExecuteNonQuery();

Implements

IDbCommand.ExecuteNonQuery

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13. ExecuteReader Method

Overload List

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1. MySqlCommand.ExecuteReader Method

Syntax: Visual Basic

Overloads Public Function ExecuteReader() As MySqlDataReader

Syntax: C#

public MySqlDataReader ExecuteReader();

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace , MySqlCommand.ExecuteReader Overload List

27.2.4.1.2.1.13.1.1. MySqlDataReader Class

Provides a means of reading a forward-only stream of rows from a MySQL database. This class cannot be inherited.

For a list of all members of this type, see MySqlDataReader Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlDataReader_
  Inherits MarshalByRefObject_
  Implements IEnumerable, IDataReader, IDisposable, IDataRecord

Syntax: C#

public sealed class MySqlDataReader : MarshalByRefObject, IEnumerable, IDataReader, IDisposable, IDataRecord

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlDataReader Members , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1. MySqlDataReader Members

MySqlDataReader overview

Public Instance Properties

DepthGets a value indicating the depth of nesting for the current row. This method is not supported currently and always returns 0.
FieldCountGets the number of columns in the current row.
HasRowsGets a value indicating whether the MySqlDataReader contains one or more rows.
IsClosedGets a value indicating whether the data reader is closed.
ItemOverloaded. Overloaded. Gets the value of a column in its native format. In C#, this property is the indexer for the MySqlDataReader class.
RecordsAffectedGets the number of rows changed, inserted, or deleted by execution of the SQL statement.

Public Instance Methods

CloseCloses the MySqlDataReader object.
CreateObjRef(inherited from MarshalByRefObject)Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetBooleanGets the value of the specified column as a Boolean.
GetByteGets the value of the specified column as a byte.
GetBytesReads a stream of bytes from the specified column offset into the buffer an array starting at the given buffer offset.
GetCharGets the value of the specified column as a single character.
GetCharsReads a stream of characters from the specified column offset into the buffer as an array starting at the given buffer offset.
GetDataTypeNameGets the name of the source data type.
GetDateTime 
GetDecimal 
GetDouble 
GetFieldTypeGets the Type that is the data type of the object.
GetFloat 
GetGuid 
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetInt16 
GetInt32 
GetInt64 
GetLifetimeService(inherited from MarshalByRefObject)Retrieves the current lifetime service object that controls the lifetime policy for this instance.
GetMySqlDateTime 
GetNameGets the name of the specified column.
GetOrdinalGets the column ordinal, given the name of the column.
GetSchemaTableReturns a DataTable that describes the column metadata of the MySqlDataReader.
GetString 
GetTimeSpan 
GetType(inherited from Object)Gets the Typeof the current instance.
GetUInt16 
GetUInt32 
GetUInt64 
GetValueGets the value of the specified column in its native format.
GetValuesGets all attribute columns in the collection for the current row.
InitializeLifetimeService(inherited from MarshalByRefObject)Obtains a lifetime service object to control the lifetime policy for this instance.
IsDBNullGets a value indicating whether the column contains non-existent or missing values.
NextResultAdvances the data reader to the next result, when reading the results of batch SQL statements.
ReadAdvances the MySqlDataReader to the next record.
ToString(inherited from Object)Returns a Stringthat represents the current Object.

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.1. Depth Property

Gets a value indicating the depth of nesting for the current row. This method is not supported currently and always returns 0.

Syntax: Visual Basic

NotOverridable Public ReadOnly Property Depth As Integer _
_
  Implements IDataReader.Depth

Syntax: C#

public int Depth {get;}

Implements

IDataReader.Depth

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.2. FieldCount Property

Gets the number of columns in the current row.

Syntax: Visual Basic

NotOverridable Public ReadOnly Property FieldCount As Integer _
_
  Implements IDataRecord.FieldCount

Syntax: C#

public int FieldCount {get;}

Implements

IDataRecord.FieldCount

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.3. HasRows Property

Gets a value indicating whether the MySqlDataReader contains one or more rows.

Syntax: Visual Basic

Public ReadOnly Property HasRows As Boolean

Syntax: C#

public bool HasRows {get;}

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.4. IsClosed Property

Gets a value indicating whether the data reader is closed.

Syntax: Visual Basic

NotOverridable Public ReadOnly Property IsClosed As Boolean _
_
  Implements IDataReader.IsClosed

Syntax: C#

public bool IsClosed {get;}

Implements

IDataReader.IsClosed

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.5. Item Property

Overloaded. Gets the value of a column in its native format. In C#, this property is the indexer for the MySqlDataReader class.

Overload List

Overloaded. Gets the value of a column in its native format. In C#, this property is the indexer for the MySqlDataReader class.

Gets the value of a column in its native format. In C#, this property is the indexer for the MySqlDataReader class.

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.5.1. Item Property (Int32)

Overloaded. Gets the value of a column in its native format. In C#, this property is the indexer for the MySqlDataReader class.

Syntax: Visual Basic

NotOverridable Overloads Public Default ReadOnly Property Item( _
   ByVal i As Integer _
) _
_
  Implements IDataRecord.Item As Object _
_
  Implements IDataRecord.Item

Syntax: C#

public object this[
inti
] {get;}

Implements

IDataRecord.Item

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace , MySqlDataReader.Item Overload List

27.2.4.1.2.1.13.1.1.1.5.2. Item Property (String)

Gets the value of a column in its native format. In C#, this property is the indexer for the MySqlDataReader class.

Syntax: Visual Basic

NotOverridable Overloads Public Default ReadOnly Property Item( _
   ByVal name As String _
) _
_
  Implements IDataRecord.Item As Object _
_
  Implements IDataRecord.Item

Syntax: C#

public object this[
stringname
] {get;}

Implements

IDataRecord.Item

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace , MySqlDataReader.Item Overload List

27.2.4.1.2.1.13.1.1.1.6. RecordsAffected Property

Gets the number of rows changed, inserted, or deleted by execution of the SQL statement.

Syntax: Visual Basic

NotOverridable Public ReadOnly Property RecordsAffected As Integer _
_
  Implements IDataReader.RecordsAffected

Syntax: C#

public int RecordsAffected {get;}

Implements

IDataReader.RecordsAffected

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.7. MySqlDataReader.Close Method

Closes the MySqlDataReader object.

Syntax: Visual Basic

NotOverridable Public Sub Close() _
_
  Implements IDataReader.Close

Syntax: C#

public void Close();

Implements

IDataReader.Close

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.8. MySqlDataReader.GetBoolean Method

Gets the value of the specified column as a Boolean.

Syntax: Visual Basic

NotOverridable Public Function GetBoolean( _
   ByVal i As Integer _
) As Boolean _
_
  Implements IDataRecord.GetBoolean

Syntax: C#

public bool GetBoolean(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.GetBoolean

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.9. MySqlDataReader.GetByte Method

Gets the value of the specified column as a byte.

Syntax: Visual Basic

NotOverridable Public Function GetByte( _
   ByVal i As Integer _
) As Byte _
_
  Implements IDataRecord.GetByte

Syntax: C#

public byte GetByte(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.GetByte

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.10. MySqlDataReader.GetBytes Method

Reads a stream of bytes from the specified column offset into the buffer an array starting at the given buffer offset.

Syntax: Visual Basic

NotOverridable Public Function GetBytes( _
   ByVal i As Integer, _
   ByVal dataIndex As Long, _
   ByVal buffer As Byte(), _
   ByVal bufferIndex As Integer, _
   ByVal length As Integer _
) As Long _
_
  Implements IDataRecord.GetBytes

Syntax: C#

public long GetBytes(
inti,
longdataIndex,
byte[]buffer,
intbufferIndex,
intlength
);

Parameters

  • i: The zero-based column ordinal.

  • dataIndex: The index within the field from which to begin the read operation.

  • buffer: The buffer into which to read the stream of bytes.

  • bufferIndex: The index for buffer to begin the read operation.

  • length: The maximum length to copy into the buffer.

Return Value

The actual number of bytes read.

Implements

IDataRecord.GetBytes

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.11. MySqlDataReader.GetChar Method

Gets the value of the specified column as a single character.

Syntax: Visual Basic

NotOverridable Public Function GetChar( _
   ByVal i As Integer _
) As Char _
_
  Implements IDataRecord.GetChar

Syntax: C#

public char GetChar(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.GetChar

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.12. MySqlDataReader.GetChars Method

Reads a stream of characters from the specified column offset into the buffer as an array starting at the given buffer offset.

Syntax: Visual Basic

NotOverridable Public Function GetChars( _
   ByVal i As Integer, _
   ByVal fieldOffset As Long, _
   ByVal buffer As Char(), _
   ByVal bufferoffset As Integer, _
   ByVal length As Integer _
) As Long _
_
  Implements IDataRecord.GetChars

Syntax: C#

public long GetChars(
inti,
longfieldOffset,
char[]buffer,
intbufferoffset,
intlength
);

Parameters

  • i:

  • fieldOffset:

  • buffer:

  • bufferoffset:

  • length:

Return Value

Implements

IDataRecord.GetChars

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.13. MySqlDataReader.GetDataTypeName Method

Gets the name of the source data type.

Syntax: Visual Basic

NotOverridable Public Function GetDataTypeName( _
   ByVal i As Integer _
) As String _
_
  Implements IDataRecord.GetDataTypeName

Syntax: C#

public string GetDataTypeName(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.GetDataTypeName

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.14. MySqlDataReader.GetDateTime Method

Syntax: Visual Basic

NotOverridable Public Function GetDateTime( _
   ByVal index As Integer _
) As Date _
_
  Implements IDataRecord.GetDateTime

Syntax: C#

public DateTime GetDateTime(
intindex
);

Implements

IDataRecord.GetDateTime

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.15. MySqlDataReader.GetDecimal Method

Syntax: Visual Basic

NotOverridable Public Function GetDecimal( _
   ByVal index As Integer _
) As Decimal _
_
  Implements IDataRecord.GetDecimal

Syntax: C#

public decimal GetDecimal(
intindex
);

Implements

IDataRecord.GetDecimal

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.16. MySqlDataReader.GetDouble Method

Syntax: Visual Basic

NotOverridable Public Function GetDouble( _
   ByVal index As Integer _
) As Double _
_
  Implements IDataRecord.GetDouble

Syntax: C#

public double GetDouble(
intindex
);

Implements

IDataRecord.GetDouble

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.17. MySqlDataReader.GetFieldType Method

Gets the Type that is the data type of the object.

Syntax: Visual Basic

NotOverridable Public Function GetFieldType( _
   ByVal i As Integer _
) As Type _
_
  Implements IDataRecord.GetFieldType

Syntax: C#

public Type GetFieldType(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.GetFieldType

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.18. MySqlDataReader.GetFloat Method

Syntax: Visual Basic

NotOverridable Public Function GetFloat( _
   ByVal index As Integer _
) As Single _
_
  Implements IDataRecord.GetFloat

Syntax: C#

public float GetFloat(
intindex
);

Implements

IDataRecord.GetFloat

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.19. MySqlDataReader.GetGuid Method

Syntax: Visual Basic

NotOverridable Public Function GetGuid( _
   ByVal index As Integer _
) As Guid _
_
  Implements IDataRecord.GetGuid

Syntax: C#

public Guid GetGuid(
intindex
);

Implements

IDataRecord.GetGuid

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.20. MySqlDataReader.GetInt16 Method

Syntax: Visual Basic

NotOverridable Public Function GetInt16( _
   ByVal index As Integer _
) As Short _
_
  Implements IDataRecord.GetInt16

Syntax: C#

public short GetInt16(
intindex
);

Implements

IDataRecord.GetInt16

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.21. MySqlDataReader.GetInt32 Method

Syntax: Visual Basic

NotOverridable Public Function GetInt32( _
   ByVal index As Integer _
) As Integer _
_
  Implements IDataRecord.GetInt32

Syntax: C#

public int GetInt32(
intindex
);

Implements

IDataRecord.GetInt32

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.22. MySqlDataReader.GetInt64 Method

Syntax: Visual Basic

NotOverridable Public Function GetInt64( _
   ByVal index As Integer _
) As Long _
_
  Implements IDataRecord.GetInt64

Syntax: C#

public long GetInt64(
intindex
);

Implements

IDataRecord.GetInt64

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.23. MySqlDataReader.GetMySqlDateTime Method

Syntax: Visual Basic

Public Function GetMySqlDateTime( _
   ByVal index As Integer _
) As MySqlDateTime

Syntax: C#

public MySqlDateTime GetMySqlDateTime(
intindex
);

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.24. MySqlDataReader.GetName Method

Gets the name of the specified column.

Syntax: Visual Basic

NotOverridable Public Function GetName( _
   ByVal i As Integer _
) As String _
_
  Implements IDataRecord.GetName

Syntax: C#

public string GetName(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.GetName

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.25. MySqlDataReader.GetOrdinal Method

Gets the column ordinal, given the name of the column.

Syntax: Visual Basic

NotOverridable Public Function GetOrdinal( _
   ByVal name As String _
) As Integer _
_
  Implements IDataRecord.GetOrdinal

Syntax: C#

public int GetOrdinal(
stringname
);

Parameters

  • name:

Return Value

Implements

IDataRecord.GetOrdinal

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.26. MySqlDataReader.GetSchemaTable Method

Returns a DataTable that describes the column metadata of the MySqlDataReader.

Syntax: Visual Basic

NotOverridable Public Function GetSchemaTable() As DataTable _
_
  Implements IDataReader.GetSchemaTable

Syntax: C#

public DataTable GetSchemaTable();

Return Value

Implements

IDataReader.GetSchemaTable

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.27. MySqlDataReader.GetString Method

Syntax: Visual Basic

NotOverridable Public Function GetString( _
   ByVal index As Integer _
) As String _
_
  Implements IDataRecord.GetString

Syntax: C#

public string GetString(
intindex
);

Implements

IDataRecord.GetString

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.28. MySqlDataReader.GetTimeSpan Method

Syntax: Visual Basic

Public Function GetTimeSpan( _
   ByVal index As Integer _
) As TimeSpan

Syntax: C#

public TimeSpan GetTimeSpan(
intindex
);

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.29. MySqlDataReader.GetUInt16 Method

Syntax: Visual Basic

Public Function GetUInt16( _
   ByVal index As Integer _
) As UInt16

Syntax: C#

public ushort GetUInt16(
intindex
);

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.30. MySqlDataReader.GetUInt32 Method

Syntax: Visual Basic

Public Function GetUInt32( _
   ByVal index As Integer _
) As UInt32

Syntax: C#

public uint GetUInt32(
intindex
);

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.31. MySqlDataReader.GetUInt64 Method

Syntax: Visual Basic

Public Function GetUInt64( _
   ByVal index As Integer _
) As UInt64

Syntax: C#

public ulong GetUInt64(
intindex
);

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.32. MySqlDataReader.GetValue Method

Gets the value of the specified column in its native format.

Syntax: Visual Basic

NotOverridable Public Function GetValue( _
   ByVal i As Integer _
) As Object _
_
  Implements IDataRecord.GetValue

Syntax: C#

public object GetValue(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.GetValue

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.33. MySqlDataReader.GetValues Method

Gets all attribute columns in the collection for the current row.

Syntax: Visual Basic

NotOverridable Public Function GetValues( _
   ByVal values As Object() _
) As Integer _
_
  Implements IDataRecord.GetValues

Syntax: C#

public int GetValues(
object[]values
);

Parameters

  • values:

Return Value

Implements

IDataRecord.GetValues

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.34. MySqlDataReader.IsDBNull Method

Gets a value indicating whether the column contains non-existent or missing values.

Syntax: Visual Basic

NotOverridable Public Function IsDBNull( _
   ByVal i As Integer _
) As Boolean _
_
  Implements IDataRecord.IsDBNull

Syntax: C#

public bool IsDBNull(
inti
);

Parameters

  • i:

Return Value

Implements

IDataRecord.IsDBNull

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.35. MySqlDataReader.NextResult Method

Advances the data reader to the next result, when reading the results of batch SQL statements.

Syntax: Visual Basic

NotOverridable Public Function NextResult() As Boolean _
_
  Implements IDataReader.NextResult

Syntax: C#

public bool NextResult();

Return Value

Implements

IDataReader.NextResult

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.1.1.1.36. MySqlDataReader.Read Method

Advances the MySqlDataReader to the next record.

Syntax: Visual Basic

NotOverridable Public Function Read() As Boolean _
_
  Implements IDataReader.Read

Syntax: C#

public bool Read();

Return Value

Implements

IDataReader.Read

See Also

MySqlDataReader Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.13.2. MySqlCommand.ExecuteReader Method

Syntax: Visual Basic

Overloads Public Function ExecuteReader( _
   ByVal behavior As CommandBehavior _
) As MySqlDataReader

Syntax: C#

public MySqlDataReader ExecuteReader(
CommandBehaviorbehavior
);

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace , MySqlCommand.ExecuteReader Overload List

27.2.4.1.2.1.14. MySqlCommand.ExecuteScalar Method

Syntax: Visual Basic

NotOverridable Public Function ExecuteScalar() As Object _
_
  Implements IDbCommand.ExecuteScalar

Syntax: C#

public object ExecuteScalar();

Implements

IDbCommand.ExecuteScalar

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.2.1.15. MySqlCommand.Prepare Method

Syntax: Visual Basic

NotOverridable Public Sub Prepare() _
_
  Implements IDbCommand.Prepare

Syntax: C#

public void Prepare();

Implements

IDbCommand.Prepare

See Also

MySqlCommand Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3. MySqlCommandBuilder Class

For a list of all members of this type, see MySqlCommandBuilder Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlCommandBuilder_
  Inherits Component

Syntax: C#

public sealed class MySqlCommandBuilder : Component

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlCommandBuilder Members , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1. MySqlCommandBuilder Members

MySqlCommandBuilder overview

Public Static (Shared) Methods

DeriveParametersOverloaded. Retrieves parameter information from the stored procedure specified in the MySqlCommand and populates the Parameters collection of the specified MySqlCommand object. This method is not currently supported since stored procedures are not available in MySql.

Public Instance Constructors

MySqlCommandBuilderOverloaded. Initializes a new instance of the MySqlCommandBuilder class.

Public Instance Properties

Container(inherited from Component)Gets the IContainerthat contains the Component.
DataAdapter 
QuotePrefix 
QuoteSuffix 
Site(inherited from Component)Gets or sets the ISiteof the Component.

Public Instance Methods

CreateObjRef(inherited from MarshalByRefObject)Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.
Dispose(inherited from Component)Releases all resources used by the Component.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetDeleteCommand 
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetInsertCommand 
GetLifetimeService(inherited from MarshalByRefObject)Retrieves the current lifetime service object that controls the lifetime policy for this instance.
GetType(inherited from Object)Gets the Typeof the current instance.
GetUpdateCommand 
InitializeLifetimeService(inherited from MarshalByRefObject)Obtains a lifetime service object to control the lifetime policy for this instance.
RefreshSchema 
ToString(inherited from Component)Returns a Stringcontaining the name of the Component, if any. This method should not be overridden.

Public Instance Events

Disposed(inherited from Component)Adds an event handler to listen to the Disposedevent on the component.

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.1. DeriveParameters Method

Retrieves parameter information from the stored procedure specified in the MySqlCommand and populates the Parameters collection of the specified MySqlCommand object. This method is not currently supported since stored procedures are not available in MySql.

Overload List

Retrieves parameter information from the stored procedure specified in the MySqlCommand and populates the Parameters collection of the specified MySqlCommand object. This method is not currently supported since stored procedures are not available in MySql.

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.1.1. MySqlCommandBuilder.DeriveParameters Method

Retrieves parameter information from the stored procedure specified in the MySqlCommand and populates the Parameters collection of the specified MySqlCommand object. This method is not currently supported since stored procedures are not available in MySql.

Syntax: Visual Basic

Overloads Public Shared Sub DeriveParameters( _
   ByVal command As MySqlCommand _
)

Syntax: C#

public static void DeriveParameters(
MySqlCommandcommand
);

Parameters

  • command: The MySqlCommand referencing the stored procedure from which the parameter information is to be derived. The derived parameters are added to the Parameters collection of the MySqlCommand.

Exceptions

Exception TypeCondition
InvalidOperationExceptionThe command text is not a valid stored procedure name.

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace , MySqlCommandBuilder.DeriveParameters Overload List

27.2.4.1.3.1.1.2. MySqlCommandBuilder.DeriveParameters Method

Syntax: Visual Basic

Overloads Public Shared Sub DeriveParameters( _
   ByVal command As MySqlCommand, _
   ByVal useProc As Boolean _
)

Syntax: C#

public static void DeriveParameters(
MySqlCommandcommand,
booluseProc
);

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace , MySqlCommandBuilder.DeriveParameters Overload List

27.2.4.1.3.1.2. MySqlCommandBuilder Constructor

Initializes a new instance of the MySqlCommandBuilder class.

Overload List

Initializes a new instance of the MySqlCommandBuilder class.

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.1. MySqlCommandBuilder Constructor

Initializes a new instance of the MySqlCommandBuilder class.

Syntax: Visual Basic

Overloads Public Sub New()

Syntax: C#

public MySqlCommandBuilder();

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace , MySqlCommandBuilder Constructor Overload List

27.2.4.1.3.1.2.2. MySqlCommandBuilder Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal adapter As MySqlDataAdapter _
)

Syntax: C#

public MySqlCommandBuilder(
MySqlDataAdapteradapter
);

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace , MySqlCommandBuilder Constructor Overload List

27.2.4.1.3.1.2.2.1. MySqlDataAdapter Class

For a list of all members of this type, see MySqlDataAdapter Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlDataAdapter_
  Inherits DbDataAdapter

Syntax: C#

public sealed class MySqlDataAdapter : DbDataAdapter

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlDataAdapter Members , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1. MySqlDataAdapter Members

MySqlDataAdapter overview

Public Instance Constructors

MySqlDataAdapterOverloaded. Initializes a new instance of the MySqlDataAdapter class.

Public Instance Properties

AcceptChangesDuringFill(inherited from DataAdapter)Gets or sets a value indicating whether AcceptChangesis called on a DataRowafter it is added to the DataTableduring any of the Fill operations.
AcceptChangesDuringUpdate(inherited from DataAdapter)Gets or sets whether AcceptChangesis called during a Update.
Container(inherited from Component)Gets the IContainerthat contains the Component.
ContinueUpdateOnError(inherited from DataAdapter)Gets or sets a value that specifies whether to generate an exception when an error is encountered during a row update.
DeleteCommandOverloaded.
FillLoadOption(inherited from DataAdapter)Gets or sets the LoadOptionthat determines how the adapter fills the DataTablefrom the DbDataReader.
InsertCommandOverloaded.
MissingMappingAction(inherited from DataAdapter)Determines the action to take when incoming data does not have a matching table or column.
MissingSchemaAction(inherited from DataAdapter)Determines the action to take when existing DataSetschema does not match incoming data.
ReturnProviderSpecificTypes(inherited from DataAdapter)Gets or sets whether the Fillmethod should return provider-specific values or common CLS-compliant values.
SelectCommandOverloaded.
Site(inherited from Component)Gets or sets the ISiteof the Component.
TableMappings(inherited from DataAdapter)Gets a collection that provides the master mapping between a source table and a DataTable.
UpdateBatchSize(inherited from DbDataAdapter)Gets or sets a value that enables or disables batch processing support, and specifies the number of commands that can be executed in a batch.
UpdateCommandOverloaded.

Public Instance Methods

CreateObjRef(inherited from MarshalByRefObject)Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.
Dispose(inherited from Component)Releases all resources used by the Component.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
Fill(inherited from DbDataAdapter)Overloaded. Adds or refreshes rows in the DataSetto match those in the data source using the DataSetname, and creates a DataTablenamed "Table."
FillSchema(inherited from DbDataAdapter)Overloaded. Configures the schema of the specified DataTablebased on the specified SchemaType.
GetFillParameters(inherited from DbDataAdapter)Gets the parameters set by the user when executing an SQL SELECT statement.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetLifetimeService(inherited from MarshalByRefObject)Retrieves the current lifetime service object that controls the lifetime policy for this instance.
GetType(inherited from Object)Gets the Typeof the current instance.
InitializeLifetimeService(inherited from MarshalByRefObject)Obtains a lifetime service object to control the lifetime policy for this instance.
ResetFillLoadOption(inherited from DataAdapter)Resets FillLoadOptionto its default state and causes Fillto honor AcceptChangesDuringFill.
ShouldSerializeAcceptChangesDuringFill(inherited from DataAdapter)Determines whether the AcceptChangesDuringFillproperty should be persisted.
ShouldSerializeFillLoadOption(inherited from DataAdapter)Determines whether the FillLoadOptionproperty should be persisted.
ToString(inherited from Component)Returns a Stringcontaining the name of the Component, if any. This method should not be overridden.
Update(inherited from DbDataAdapter)Overloaded. Calls the respective INSERT, UPDATE, or DELETE statements for each inserted, updated, or deleted row in the specified DataSet.

Public Instance Events

Disposed(inherited from Component)Adds an event handler to listen to the Disposedevent on the component.
FillError(inherited from DataAdapter)Returned when an error occurs during a fill operation.
RowUpdatedOccurs during Update after a command is executed against the data source. The attempt to update is made, so the event fires.
RowUpdatingOccurs during Update before a command is executed against the data source. The attempt to update is made, so the event fires.

Protected Internal Instance Properties

FillCommandBehavior(inherited from DbDataAdapter)Gets or sets the behavior of the command used to fill the data adapter.

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.1. MySqlDataAdapter Constructor

Initializes a new instance of the MySqlDataAdapter class.

Overload List

Initializes a new instance of the MySqlDataAdapter class.

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.1.1. MySqlDataAdapter Constructor

Initializes a new instance of the MySqlDataAdapter class.

Syntax: Visual Basic

Overloads Public Sub New()

Syntax: C#

public MySqlDataAdapter();

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace , MySqlDataAdapter Constructor Overload List

27.2.4.1.3.1.2.2.1.1.1.2. MySqlDataAdapter Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal selectCommand As MySqlCommand _
)

Syntax: C#

public MySqlDataAdapter(
MySqlCommandselectCommand
);

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace , MySqlDataAdapter Constructor Overload List

27.2.4.1.3.1.2.2.1.1.1.3. MySqlDataAdapter Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal selectCommandText As String, _
   ByVal connection As MySqlConnection _
)

Syntax: C#

public MySqlDataAdapter(
stringselectCommandText,
MySqlConnectionconnection
);

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace , MySqlDataAdapter Constructor Overload List

27.2.4.1.3.1.2.2.1.1.1.4. MySqlDataAdapter Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal selectCommandText As String, _
   ByVal selectConnString As String _
)

Syntax: C#

public MySqlDataAdapter(
stringselectCommandText,
stringselectConnString
);

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace , MySqlDataAdapter Constructor Overload List

27.2.4.1.3.1.2.2.1.1.2. DeleteCommand Property

Syntax: Visual Basic

Overloads Public Property DeleteCommand As MySqlCommand

Syntax: C#

new public MySqlCommand DeleteCommand {get; set;}

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.3. InsertCommand Property

Syntax: Visual Basic

Overloads Public Property InsertCommand As MySqlCommand

Syntax: C#

new public MySqlCommand InsertCommand {get; set;}

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.4. SelectCommand Property

Syntax: Visual Basic

Overloads Public Property SelectCommand As MySqlCommand

Syntax: C#

new public MySqlCommand SelectCommand {get; set;}

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.5. UpdateCommand Property

Syntax: Visual Basic

Overloads Public Property UpdateCommand As MySqlCommand

Syntax: C#

new public MySqlCommand UpdateCommand {get; set;}

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.6. MySqlDataAdapter.RowUpdated Event

Occurs during Update after a command is executed against the data source. The attempt to update is made, so the event fires.

Syntax: Visual Basic

Public Event RowUpdated As MySqlRowUpdatedEventHandler

Syntax: C#

public event MySqlRowUpdatedEventHandler RowUpdated;

Event Data

The event handler receives an argument of type MySqlRowUpdatedEventArgs containing data related to this event. The following MySqlRowUpdatedEventArgsproperties provide information specific to this event.

PropertyDescription
CommandGets or sets the MySqlCommand executed when Update is called.
ErrorsGets any errors generated by the .NET Framework data provider when the Commandwas executed.
RecordsAffectedGets the number of rows changed, inserted, or deleted by execution of the SQL statement.
RowGets the DataRowsent through an Update.
RowCountGets the number of rows processed in a batch of updated records.
StatementTypeGets the type of SQL statement executed.
StatusGets the UpdateStatusof the Commandproperty.
TableMappingGets the DataTableMappingsent through an Update.

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.6.1. MySqlRowUpdatedEventHandler Delegate

Represents the method that will handle the RowUpdatedevent of a MySqlDataAdapter .

Syntax: Visual Basic

Public Delegate Sub MySqlRowUpdatedEventHandler( _
   ByVal sender As Object, _
   ByVal e As MySqlRowUpdatedEventArgs _
)

Syntax: C#

public delegate void MySqlRowUpdatedEventHandler(
objectsender,
MySqlRowUpdatedEventArgse
);

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.6.1.1. MySqlRowUpdatedEventArgs Class

Provides data for the RowUpdated event. This class cannot be inherited.

For a list of all members of this type, see MySqlRowUpdatedEventArgs Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlRowUpdatedEventArgs_
  Inherits RowUpdatedEventArgs

Syntax: C#

public sealed class MySqlRowUpdatedEventArgs : RowUpdatedEventArgs

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlRowUpdatedEventArgs Members , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.6.1.1.1. MySqlRowUpdatedEventArgs Members

MySqlRowUpdatedEventArgs overview

Public Instance Constructors

MySqlRowUpdatedEventArgs ConstructorInitializes a new instance of the MySqlRowUpdatedEventArgs class.

Public Instance Properties

CommandOverloaded. Gets or sets the MySqlCommand executed when Update is called.
Errors(inherited from RowUpdatedEventArgs)Gets any errors generated by the .NET Framework data provider when the Commandwas executed.
RecordsAffected(inherited from RowUpdatedEventArgs)Gets the number of rows changed, inserted, or deleted by execution of the SQL statement.
Row(inherited from RowUpdatedEventArgs)Gets the DataRowsent through an Update.
RowCount(inherited from RowUpdatedEventArgs)Gets the number of rows processed in a batch of updated records.
StatementType(inherited from RowUpdatedEventArgs)Gets the type of SQL statement executed.
Status(inherited from RowUpdatedEventArgs)Gets the UpdateStatusof the Commandproperty.
TableMapping(inherited from RowUpdatedEventArgs)Gets the DataTableMappingsent through an Update.

Public Instance Methods

CopyToRows(inherited from RowUpdatedEventArgs)Overloaded. Copies references to the modified rows into the provided array.
Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
ToString(inherited from Object)Returns a Stringthat represents the current Object.

See Also

MySqlRowUpdatedEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.6.1.1.1.1. MySqlRowUpdatedEventArgs Constructor

Initializes a new instance of the MySqlRowUpdatedEventArgs class.

Syntax: Visual Basic

Public Sub New( _
   ByVal row As DataRow, _
   ByVal command As IDbCommand, _
   ByVal statementType As StatementType, _
   ByVal tableMapping As DataTableMapping _
)

Syntax: C#

public MySqlRowUpdatedEventArgs(
DataRowrow,
IDbCommandcommand,
StatementTypestatementType,
DataTableMappingtableMapping
);

Parameters

  • row: The DataRowsent through an Update.

  • command: The IDbCommandexecuted when Updateis called.

  • statementType: One of the StatementTypevalues that specifies the type of query executed.

  • tableMapping: The DataTableMappingsent through an Update.

See Also

MySqlRowUpdatedEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.6.1.1.1.2. Command Property

Gets or sets the MySqlCommand executed when Update is called.

Syntax: Visual Basic

Overloads Public ReadOnly Property Command As MySqlCommand

Syntax: C#

new public MySqlCommand Command {get;}

See Also

MySqlRowUpdatedEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.7. MySqlDataAdapter.RowUpdating Event

Occurs during Update before a command is executed against the data source. The attempt to update is made, so the event fires.

Syntax: Visual Basic

Public Event RowUpdating As MySqlRowUpdatingEventHandler

Syntax: C#

public event MySqlRowUpdatingEventHandler RowUpdating;

Event Data

The event handler receives an argument of type MySqlRowUpdatingEventArgs containing data related to this event. The following MySqlRowUpdatingEventArgsproperties provide information specific to this event.

PropertyDescription
CommandGets or sets the MySqlCommand to execute when performing the Update.
ErrorsGets any errors generated by the .NET Framework data provider when the Commandexecutes.
RowGets the DataRowthat will be sent to the server as part of an insert, update, or delete operation.
StatementTypeGets the type of SQL statement to execute.
StatusGets or sets the UpdateStatusof the Commandproperty.
TableMappingGets the DataTableMappingto send through the Update.

See Also

MySqlDataAdapter Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.7.1. MySqlRowUpdatingEventHandler Delegate

Represents the method that will handle the RowUpdatingevent of a MySqlDataAdapter .

Syntax: Visual Basic

Public Delegate Sub MySqlRowUpdatingEventHandler( _
   ByVal sender As Object, _
   ByVal e As MySqlRowUpdatingEventArgs _
)

Syntax: C#

public delegate void MySqlRowUpdatingEventHandler(
objectsender,
MySqlRowUpdatingEventArgse
);

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.7.1.1. MySqlRowUpdatingEventArgs Class

Provides data for the RowUpdating event. This class cannot be inherited.

For a list of all members of this type, see MySqlRowUpdatingEventArgs Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlRowUpdatingEventArgs_
  Inherits RowUpdatingEventArgs

Syntax: C#

public sealed class MySqlRowUpdatingEventArgs : RowUpdatingEventArgs

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlRowUpdatingEventArgs Members , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.7.1.1.1. MySqlRowUpdatingEventArgs Members

MySqlRowUpdatingEventArgs overview

Public Instance Constructors

MySqlRowUpdatingEventArgs ConstructorInitializes a new instance of the MySqlRowUpdatingEventArgs class.

Public Instance Properties

CommandOverloaded. Gets or sets the MySqlCommand to execute when performing the Update.
Errors(inherited from RowUpdatingEventArgs)Gets any errors generated by the .NET Framework data provider when the Commandexecutes.
Row(inherited from RowUpdatingEventArgs)Gets the DataRowthat will be sent to the server as part of an insert, update, or delete operation.
StatementType(inherited from RowUpdatingEventArgs)Gets the type of SQL statement to execute.
Status(inherited from RowUpdatingEventArgs)Gets or sets the UpdateStatusof the Commandproperty.
TableMapping(inherited from RowUpdatingEventArgs)Gets the DataTableMappingto send through the Update.

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
ToString(inherited from Object)Returns a Stringthat represents the current Object.

See Also

MySqlRowUpdatingEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.7.1.1.1.1. MySqlRowUpdatingEventArgs Constructor

Initializes a new instance of the MySqlRowUpdatingEventArgs class.

Syntax: Visual Basic

Public Sub New( _
   ByVal row As DataRow, _
   ByVal command As IDbCommand, _
   ByVal statementType As StatementType, _
   ByVal tableMapping As DataTableMapping _
)

Syntax: C#

public MySqlRowUpdatingEventArgs(
DataRowrow,
IDbCommandcommand,
StatementTypestatementType,
DataTableMappingtableMapping
);

Parameters

  • row: The DataRowto Update.

  • command: The IDbCommandto execute during Update.

  • statementType: One of the StatementTypevalues that specifies the type of query executed.

  • tableMapping: The DataTableMappingsent through an Update.

See Also

MySqlRowUpdatingEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.2.1.1.7.1.1.1.2. Command Property

Gets or sets the MySqlCommand to execute when performing the Update.

Syntax: Visual Basic

Overloads Public Property Command As MySqlCommand

Syntax: C#

new public MySqlCommand Command {get; set;}

See Also

MySqlRowUpdatingEventArgs Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.2.3. MySqlCommandBuilder Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal adapter As MySqlDataAdapter, _
   ByVal lastOneWins As Boolean _
)

Syntax: C#

public MySqlCommandBuilder(
MySqlDataAdapteradapter,
boollastOneWins
);

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace , MySqlCommandBuilder Constructor Overload List

27.2.4.1.3.1.2.4. MySqlCommandBuilder Constructor

Syntax: Visual Basic

Overloads Public Sub New( _
   ByVal lastOneWins As Boolean _
)

Syntax: C#

public MySqlCommandBuilder(
boollastOneWins
);

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace , MySqlCommandBuilder Constructor Overload List

27.2.4.1.3.1.3. DataAdapter Property

Syntax: Visual Basic

Public Property DataAdapter As MySqlDataAdapter

Syntax: C#

public MySqlDataAdapter DataAdapter {get; set;}

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.4. QuotePrefix Property

Syntax: Visual Basic

Public Property QuotePrefix As String

Syntax: C#

public string QuotePrefix {get; set;}

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.5. QuoteSuffix Property

Syntax: Visual Basic

Public Property QuoteSuffix As String

Syntax: C#

public string QuoteSuffix {get; set;}

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.6. MySqlCommandBuilder.GetDeleteCommand Method

Syntax: Visual Basic

Public Function GetDeleteCommand() As MySqlCommand

Syntax: C#

public MySqlCommand GetDeleteCommand();

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.7. MySqlCommandBuilder.GetInsertCommand Method

Syntax: Visual Basic

Public Function GetInsertCommand() As MySqlCommand

Syntax: C#

public MySqlCommand GetInsertCommand();

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.8. MySqlCommandBuilder.GetUpdateCommand Method

Syntax: Visual Basic

Public Function GetUpdateCommand() As MySqlCommand

Syntax: C#

public MySqlCommand GetUpdateCommand();

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.3.1.9. MySqlCommandBuilder.RefreshSchema Method

Syntax: Visual Basic

Public Sub RefreshSchema()

Syntax: C#

public void RefreshSchema();

See Also

MySqlCommandBuilder Class , MySql.Data.MySqlClient Namespace

27.2.4.1.4. MySqlException Class

The exception that is thrown when MySQL returns an error. This class cannot be inherited.

For a list of all members of this type, see MySqlException Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlException_
  Inherits SystemException

Syntax: C#

public sealed class MySqlException : SystemException

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlException Members , MySql.Data.MySqlClient Namespace

27.2.4.1.4.1. MySqlException Members

MySqlException overview

Public Instance Properties

Data(inherited from Exception)Gets a collection of key/value pairs that provide additional, user-defined information about the exception.
HelpLink(inherited from Exception)Gets or sets a link to the help file associated with this exception.
InnerException(inherited from Exception)Gets the Exceptioninstance that caused the current exception.
Message(inherited from Exception)Gets a message that describes the current exception.
NumberGets a number that identifies the type of error.
Source(inherited from Exception)Gets or sets the name of the application or the object that causes the error.
StackTrace(inherited from Exception)Gets a string representation of the frames on the call stack at the time the current exception was thrown.
TargetSite(inherited from Exception)Gets the method that throws the current exception.

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetBaseException(inherited from Exception)When overridden in a derived class, returns the Exceptionthat is the root cause of one or more subsequent exceptions.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetObjectData(inherited from Exception)When overridden in a derived class, sets the SerializationInfowith information about the exception.
GetType(inherited from Exception)Gets the runtime type of the current instance.
ToString(inherited from Exception)Creates and returns a string representation of the current exception.

See Also

MySqlException Class , MySql.Data.MySqlClient Namespace

27.2.4.1.4.1.1. Number Property

Gets a number that identifies the type of error.

Syntax: Visual Basic

Public ReadOnly Property Number As Integer

Syntax: C#

public int Number {get;}

See Also

MySqlException Class , MySql.Data.MySqlClient Namespace

27.2.4.1.5. MySqlHelper Class

Helper class that makes it easier to work with the provider.

For a list of all members of this type, see MySqlHelper Members .

Syntax: Visual Basic

NotInheritable Public Class MySqlHelper

Syntax: C#

public sealed class MySqlHelper

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlHelper Members , MySql.Data.MySqlClient Namespace

27.2.4.1.5.1. MySqlHelper Members

MySqlHelper overview

Public Static (Shared) Methods

ExecuteDataRowExecutes a single SQL statement and returns the first row of the resultset. A new MySqlConnection object is created, opened, and closed during this method.
ExecuteDatasetOverloaded. Executes a single SQL statement and returns the resultset in a DataSet. A new MySqlConnection object is created, opened, and closed during this method.
ExecuteNonQueryOverloaded. Executes a single command against a MySQL database. The MySqlConnection is assumed to be open when the method is called and remains open after the method completes.
ExecuteReaderOverloaded. Executes a single command against a MySQL database.
ExecuteScalarOverloaded. Execute a single command against a MySQL database.
UpdateDataSetUpdates the given table with data from the given DataSet

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
ToString(inherited from Object)Returns a Stringthat represents the current Object.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace

27.2.4.1.5.1.1. MySqlHelper.ExecuteDataRow Method

Executes a single SQL statement and returns the first row of the resultset. A new MySqlConnection object is created, opened, and closed during this method.

Syntax: Visual Basic

Public Shared Function ExecuteDataRow( _
   ByVal connectionString As String, _
   ByVal commandText As String, _
   ParamArray parms As MySqlParameter() _
) As DataRow

Syntax: C#

public static DataRow ExecuteDataRow(
stringconnectionString,
stringcommandText,
   params MySqlParameter[]parms
);

Parameters

  • connectionString: Settings to be used for the connection

  • commandText: Command to execute

  • parms: Parameters to use for the command

Return Value

DataRow containing the first row of the resultset

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace

27.2.4.1.5.1.2. ExecuteDataset Method

Executes a single SQL statement and returns the resultset in a DataSet. The state of the MySqlConnection object remains unchanged after execution of this method.

Overload List

Executes a single SQL statement and returns the resultset in a DataSet. The state of the MySqlConnection object remains unchanged after execution of this method.

Executes a single SQL statement and returns the resultset in a DataSet. The state of the MySqlConnection object remains unchanged after execution of this method.

Executes a single SQL statement and returns the resultset in a DataSet. A new MySqlConnection object is created, opened, and closed during this method.

Executes a single SQL statement and returns the resultset in a DataSet. A new MySqlConnection object is created, opened, and closed during this method.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace

27.2.4.1.5.1.2.1. MySqlHelper.ExecuteDataset Method

Executes a single SQL statement and returns the resultset in a DataSet. The state of the MySqlConnection object remains unchanged after execution of this method.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteDataset( _
   ByVal connection As MySqlConnection, _
   ByVal commandText As String _
) As DataSet

Syntax: C#

public static DataSet ExecuteDataset(
MySqlConnectionconnection,
stringcommandText
);

Parameters

  • connection: MySqlConnection object to use

  • commandText: Command to execute

Return Value

DataSetcontaining the resultset

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteDataset Overload List

27.2.4.1.5.1.2.2. MySqlHelper.ExecuteDataset Method

Executes a single SQL statement and returns the resultset in a DataSet. The state of the MySqlConnection object remains unchanged after execution of this method.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteDataset( _
   ByVal connection As MySqlConnection, _
   ByVal commandText As String, _
   ParamArray commandParameters As MySqlParameter() _
) As DataSet

Syntax: C#

public static DataSet ExecuteDataset(
MySqlConnectionconnection,
stringcommandText,
   params MySqlParameter[]commandParameters
);

Parameters

  • connection: MySqlConnection object to use

  • commandText: Command to execute

  • commandParameters: Parameters to use for the command

Return Value

DataSetcontaining the resultset

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteDataset Overload List

27.2.4.1.5.1.2.3. MySqlHelper.ExecuteDataset Method

Executes a single SQL statement and returns the resultset in a DataSet. A new MySqlConnection object is created, opened, and closed during this method.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteDataset( _
   ByVal connectionString As String, _
   ByVal commandText As String _
) As DataSet

Syntax: C#

public static DataSet ExecuteDataset(
stringconnectionString,
stringcommandText
);

Parameters

  • connectionString: Settings to be used for the connection

  • commandText: Command to execute

Return Value

DataSetcontaining the resultset

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteDataset Overload List

27.2.4.1.5.1.2.4. MySqlHelper.ExecuteDataset Method

Executes a single SQL statement and returns the resultset in a DataSet. A new MySqlConnection object is created, opened, and closed during this method.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteDataset( _
   ByVal connectionString As String, _
   ByVal commandText As String, _
   ParamArray commandParameters As MySqlParameter() _
) As DataSet

Syntax: C#

public static DataSet ExecuteDataset(
stringconnectionString,
stringcommandText,
   params MySqlParameter[]commandParameters
);

Parameters

  • connectionString: Settings to be used for the connection

  • commandText: Command to execute

  • commandParameters: Parameters to use for the command

Return Value

DataSetcontaining the resultset

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteDataset Overload List

27.2.4.1.5.1.3. ExecuteNonQuery Method

Executes a single command against a MySQL database. The MySqlConnection is assumed to be open when the method is called and remains open after the method completes.

Overload List

Executes a single command against a MySQL database. The MySqlConnection is assumed to be open when the method is called and remains open after the method completes.

Executes a single command against a MySQL database. A new MySqlConnection is created using the ConnectionString given.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace

27.2.4.1.5.1.3.1. MySqlHelper.ExecuteNonQuery Method

Executes a single command against a MySQL database. The MySqlConnection is assumed to be open when the method is called and remains open after the method completes.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteNonQuery( _
   ByVal connection As MySqlConnection, _
   ByVal commandText As String, _
   ParamArray commandParameters As MySqlParameter() _
) As Integer

Syntax: C#

public static int ExecuteNonQuery(
MySqlConnectionconnection,
stringcommandText,
   params MySqlParameter[]commandParameters
);

Parameters

  • connection: MySqlConnection object to use

  • commandText: SQL statement to be executed

  • commandParameters: Array of MySqlParameter objects to use with the command.

Return Value

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteNonQuery Overload List

27.2.4.1.5.1.3.2. MySqlHelper.ExecuteNonQuery Method

Executes a single command against a MySQL database. A new MySqlConnection is created using the ConnectionString given.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteNonQuery( _
   ByVal connectionString As String, _
   ByVal commandText As String, _
   ParamArray parms As MySqlParameter() _
) As Integer

Syntax: C#

public static int ExecuteNonQuery(
stringconnectionString,
stringcommandText,
   params MySqlParameter[]parms
);

Parameters

Return Value

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteNonQuery Overload List

27.2.4.1.5.1.4. ExecuteReader Method

Executes a single command against a MySQL database.

Overload List

Executes a single command against a MySQL database.

Executes a single command against a MySQL database.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace

27.2.4.1.5.1.4.1. MySqlHelper.ExecuteReader Method

Executes a single command against a MySQL database.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteReader( _
   ByVal connectionString As String, _
   ByVal commandText As String _
) As MySqlDataReader

Syntax: C#

public static MySqlDataReader ExecuteReader(
stringconnectionString,
stringcommandText
);

Parameters

  • connectionString: Settings to use for this command

  • commandText: Command text to use

Return Value

MySqlDataReader object ready to read the results of the command

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteReader Overload List

27.2.4.1.5.1.4.2. MySqlHelper.ExecuteReader Method

Executes a single command against a MySQL database.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteReader( _
   ByVal connectionString As String, _
   ByVal commandText As String, _
   ParamArray commandParameters As MySqlParameter() _
) As MySqlDataReader

Syntax: C#

public static MySqlDataReader ExecuteReader(
stringconnectionString,
stringcommandText,
   params MySqlParameter[]commandParameters
);

Parameters

  • connectionString: Settings to use for this command

  • commandText: Command text to use

  • commandParameters: Array of MySqlParameter objects to use with the command

Return Value

MySqlDataReader object ready to read the results of the command

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteReader Overload List

27.2.4.1.5.1.5. ExecuteScalar Method

Execute a single command against a MySQL database.

Overload List

Execute a single command against a MySQL database.

Execute a single command against a MySQL database.

Execute a single command against a MySQL database.

Execute a single command against a MySQL database.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace

27.2.4.1.5.1.5.1. MySqlHelper.ExecuteScalar Method

Execute a single command against a MySQL database.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteScalar( _
   ByVal connection As MySqlConnection, _
   ByVal commandText As String _
) As Object

Syntax: C#

public static object ExecuteScalar(
MySqlConnectionconnection,
stringcommandText
);

Parameters

  • connection: MySqlConnection object to use

  • commandText: Command text to use for the command

Return Value

The first column of the first row in the result set, or a null reference if the result set is empty.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteScalar Overload List

27.2.4.1.5.1.5.2. MySqlHelper.ExecuteScalar Method

Execute a single command against a MySQL database.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteScalar( _
   ByVal connection As MySqlConnection, _
   ByVal commandText As String, _
   ParamArray commandParameters As MySqlParameter() _
) As Object

Syntax: C#

public static object ExecuteScalar(
MySqlConnectionconnection,
stringcommandText,
   params MySqlParameter[]commandParameters
);

Parameters

  • connection: MySqlConnection object to use

  • commandText: Command text to use for the command

  • commandParameters: Parameters to use for the command

Return Value

The first column of the first row in the result set, or a null reference if the result set is empty.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteScalar Overload List

27.2.4.1.5.1.5.3. MySqlHelper.ExecuteScalar Method

Execute a single command against a MySQL database.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteScalar( _
   ByVal connectionString As String, _
   ByVal commandText As String _
) As Object

Syntax: C#

public static object ExecuteScalar(
stringconnectionString,
stringcommandText
);

Parameters

  • connectionString: Settings to use for the update

  • commandText: Command text to use for the update

Return Value

The first column of the first row in the result set, or a null reference if the result set is empty.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteScalar Overload List

27.2.4.1.5.1.5.4. MySqlHelper.ExecuteScalar Method

Execute a single command against a MySQL database.

Syntax: Visual Basic

Overloads Public Shared Function ExecuteScalar( _
   ByVal connectionString As String, _
   ByVal commandText As String, _
   ParamArray commandParameters As MySqlParameter() _
) As Object

Syntax: C#

public static object ExecuteScalar(
stringconnectionString,
stringcommandText,
   params MySqlParameter[]commandParameters
);

Parameters

  • connectionString: Settings to use for the command

  • commandText: Command text to use for the command

  • commandParameters: Parameters to use for the command

Return Value

The first column of the first row in the result set, or a null reference if the result set is empty.

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace , MySqlHelper.ExecuteScalar Overload List

27.2.4.1.5.1.6. MySqlHelper.UpdateDataSet Method

Updates the given table with data from the given DataSet

Syntax: Visual Basic

Public Shared Sub UpdateDataSet( _
   ByVal connectionString As String, _
   ByVal commandText As String, _
   ByVal ds As DataSet, _
   ByVal tablename As String _
)

Syntax: C#

public static void UpdateDataSet(
stringconnectionString,
stringcommandText,
DataSetds,
stringtablename
);

Parameters

  • connectionString: Settings to use for the update

  • commandText: Command text to use for the update

  • ds: DataSetcontaining the new data to use in the update

  • tablename: Tablename in the data set to update

See Also

MySqlHelper Class , MySql.Data.MySqlClient Namespace

27.2.4.1.6. MySqlErrorCode Enumeration

Syntax: Visual Basic

Public Enum MySqlErrorCode

Syntax: C#

public enum MySqlErrorCode

Members

Member NameDescription
PacketTooLarge 
PasswordNotAllowed 
DuplicateKeyEntry 
HostNotPrivileged 
PasswordNoMatch 
AnonymousUser 
DuplicateKey 
KeyNotFound 
DuplicateKeyName 

Requirements

Namespace: MySql.Data.MySqlClient

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySql.Data.MySqlClient Namespace

27.2.4.2. MySql.Data.Types

Namespace hierarchy

Classes

ClassDescription
MySqlConversionExceptionSummary description for MySqlConversionException.
MySqlDateTimeSummary description for MySqlDateTime.
MySqlValue 
27.2.4.2.1. MySql.Data.TypesHierarchy

See Also

MySql.Data.Types Namespace

27.2.4.2.2. MySqlConversionException Class

Summary description for MySqlConversionException.

For a list of all members of this type, see MySqlConversionException Members .

Syntax: Visual Basic

Public Class MySqlConversionException_
  Inherits ApplicationException

Syntax: C#

public class MySqlConversionException : ApplicationException

Thread Safety

Public static (Sharedin Visual Basic) members of this type are safe for multithreaded operations. Instance members are notguaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.Types

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlConversionException Members , MySql.Data.Types Namespace

27.2.4.2.2.1. MySqlConversionException Members

MySqlConversionException overview

Public Instance Constructors

Public Instance Properties

Data(inherited from Exception)Gets a collection of key/value pairs that provide additional, user-defined information about the exception.
HelpLink(inherited from Exception)Gets or sets a link to the help file associated with this exception.
InnerException(inherited from Exception)Gets the Exceptioninstance that caused the current exception.
Message(inherited from Exception)Gets a message that describes the current exception.
Source(inherited from Exception)Gets or sets the name of the application or the object that causes the error.
StackTrace(inherited from Exception)Gets a string representation of the frames on the call stack at the time the current exception was thrown.
TargetSite(inherited from Exception)Gets the method that throws the current exception.

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetBaseException(inherited from Exception)When overridden in a derived class, returns the Exceptionthat is the root cause of one or more subsequent exceptions.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetObjectData(inherited from Exception)When overridden in a derived class, sets the SerializationInfowith information about the exception.
GetType(inherited from Exception)Gets the runtime type of the current instance.
ToString(inherited from Exception)Creates and returns a string representation of the current exception.

Protected Instance Properties

HResult(inherited from Exception)Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception.

Protected Instance Methods

Finalize(inherited from Object)Allows an Objectto attempt to free resources and perform other cleanup operations before the Objectis reclaimed by garbage collection.
MemberwiseClone(inherited from Object)Creates a shallow copy of the current Object.

See Also

MySqlConversionException Class , MySql.Data.Types Namespace

27.2.4.2.2.1.1. MySqlConversionException Constructor

Syntax: Visual Basic

Public Sub New( _
   ByVal msg As String _
)

Syntax: C#

public MySqlConversionException(
stringmsg
);

See Also

MySqlConversionException Class , MySql.Data.Types Namespace

27.2.4.2.3. MySqlDateTime Class

Summary description for MySqlDateTime.

For a list of all members of this type, see MySqlDateTime Members .

Syntax: Visual Basic

Public Class MySqlDateTime_
  Inherits MySqlValue_
  Implements IConvertible, IComparable

Syntax: C#

public class MySqlDateTime : MySqlValue, IConvertible, IComparable

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.Types

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlDateTime Members , MySql.Data.Types Namespace

27.2.4.2.3.1. MySqlDateTime Members

MySqlDateTime overview

Public Static (Shared) Type Conversions

Public Instance Properties

DayReturns the day portion of this datetime
HourReturns the hour portion of this datetime
IsNull (inherited from MySqlValue) 
IsValidDateTimeIndicates if this object contains a value that can be represented as a DateTime
MinuteReturns the minute portion of this datetime
MonthReturns the month portion of this datetime
SecondReturns the second portion of this datetime
ValueAsObject (inherited from MySqlValue)Returns the value of this field as an object
YearReturns the year portion of this datetime

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetDateTimeReturns this value as a DateTime
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
ToStringReturns a MySQL specific string representation of this value

Protected Instance Fields

classType (inherited from MySqlValue)The system type represented by this value
dbType (inherited from MySqlValue)The generic dbtype of this value
isNull (inherited from MySqlValue)Is this value null
mySqlDbType (inherited from MySqlValue)The specific MySQL db type
mySqlTypeName (inherited from MySqlValue)The MySQL specific typename of this value
objectValue (inherited from MySqlValue) 

Protected Instance Methods

Finalize(inherited from Object)Allows an Objectto attempt to free resources and perform other cleanup operations before the Objectis reclaimed by garbage collection.
MemberwiseClone(inherited from Object)Creates a shallow copy of the current Object.

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.1. MySqlDateTime Explicit MySqlDateTime to DateTime Conversion

Syntax: Visual Basic

MySqlDateTime.op_Explicit(val)

Syntax: C#

public static explicit operator DateTime(
MySqlDateTimeval
);

Parameters

  • val:

Return Value

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.2. Day Property

Returns the day portion of this datetime

Syntax: Visual Basic

Public Property Day As Integer

Syntax: C#

public int Day {get; set;}

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.3. Hour Property

Returns the hour portion of this datetime

Syntax: Visual Basic

Public Property Hour As Integer

Syntax: C#

public int Hour {get; set;}

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4. IsNull Property

Syntax: Visual Basic

Public Property IsNull As Boolean

Syntax: C#

public bool IsNull {get; set;}

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1. MySqlValue Class

For a list of all members of this type, see MySqlValue Members .

Syntax: Visual Basic

MustInherit Public Class MySqlValue

Syntax: C#

public abstract class MySqlValue

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Requirements

Namespace: MySql.Data.Types

Assembly: MySql.Data (in MySql.Data.dll)

See Also

MySqlValue Members , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1. MySqlValue Members

MySqlValue overview

Protected Static (Shared) Fields

Public Instance Constructors

MySqlValue ConstructorInitializes a new instance of the MySqlValue class.

Public Instance Properties

IsNull 
ValueAsObjectReturns the value of this field as an object

Public Instance Methods

Equals(inherited from Object)Determines whether the specified Objectis equal to the current Object.
GetHashCode(inherited from Object)Serves as a hash function for a particular type. GetHashCodeis suitable for use in hashing algorithms and data structures like a hash table.
GetType(inherited from Object)Gets the Typeof the current instance.
ToStringReturns a string representation of this value

Protected Instance Fields

classTypeThe system type represented by this value
dbTypeThe generic dbtype of this value
isNullIs this value null
mySqlDbTypeThe specific MySQL db type
mySqlTypeNameThe MySQL specific typename of this value
objectValue 

Protected Instance Methods

Finalize(inherited from Object)Allows an Objectto attempt to free resources and perform other cleanup operations before the Objectis reclaimed by garbage collection.
MemberwiseClone(inherited from Object)Creates a shallow copy of the current Object.

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.1. MySqlValue.numberFormat Field

Syntax: Visual Basic

Protected Shared numberFormat As NumberFormatInfo

Syntax: C#

protected static NumberFormatInfo numberFormat;

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.2. MySqlValue Constructor

Initializes a new instance of the MySqlValue class.

Syntax: Visual Basic

Public Sub New()

Syntax: C#

public MySqlValue();

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.3. ValueAsObject Property

Returns the value of this field as an object

Syntax: Visual Basic

Public ReadOnly Property ValueAsObject As Object

Syntax: C#

public object ValueAsObject {get;}

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.4. MySqlValue.ToString Method

Returns a string representation of this value

Syntax: Visual Basic

Overrides Public Function ToString() As String

Syntax: C#

public override string ToString();

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.5. MySqlValue.classType Field

The system type represented by this value

Syntax: Visual Basic

Protected classType As Type

Syntax: C#

protected Type classType;

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.6. MySqlValue.dbType Field

The generic dbtype of this value

Syntax: Visual Basic

Protected dbType As DbType

Syntax: C#

protected DbType dbType;

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.7. MySqlValue.mySqlDbType Field

The specific MySQL db type

Syntax: Visual Basic

Protected mySqlDbType As MySqlDbType

Syntax: C#

protected MySqlDbType mySqlDbType;

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.8. MySqlValue.mySqlTypeName Field

The MySQL specific typename of this value

Syntax: Visual Basic

Protected mySqlTypeName As String

Syntax: C#

protected string mySqlTypeName;

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.4.1.1.9. MySqlValue.objectValue Field

Syntax: Visual Basic

Protected objectValue As Object

Syntax: C#

protected object objectValue;

See Also

MySqlValue Class , MySql.Data.Types Namespace

27.2.4.2.3.1.5. IsValidDateTime Property

Indicates if this object contains a value that can be represented as a DateTime

Syntax: Visual Basic

Public ReadOnly Property IsValidDateTime As Boolean

Syntax: C#

public bool IsValidDateTime {get;}

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.6. Minute Property

Returns the minute portion of this datetime

Syntax: Visual Basic

Public Property Minute As Integer

Syntax: C#

public int Minute {get; set;}

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.7. Month Property

Returns the month portion of this datetime

Syntax: Visual Basic

Public Property Month As Integer

Syntax: C#

public int Month {get; set;}

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.8. Second Property

Returns the second portion of this datetime

Syntax: Visual Basic

Public Property Second As Integer

Syntax: C#

public int Second {get; set;}

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.9. Year Property

Returns the year portion of this datetime

Syntax: Visual Basic

Public Property Year As Integer

Syntax: C#

public int Year {get; set;}

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.10. MySqlDateTime.GetDateTime Method

Returns this value as a DateTime

Syntax: Visual Basic

Public Function GetDateTime() As Date

Syntax: C#

public DateTime GetDateTime();

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.4.2.3.1.11. MySqlDateTime.ToString Method

Returns a MySQL specific string representation of this value

Syntax: Visual Basic

Overrides Public Function ToString() As String

Syntax: C#

public override string ToString();

See Also

MySqlDateTime Class , MySql.Data.Types Namespace

27.2.5. Connector/NET Notes and Tips

In this section we will cover some of the more common use cases for Connector/NET, including BLOB handling, date handling, and using Connector/NET with common tools such as Crystal Reports.

27.2.5.1. Connecting to MySQL Using Connector/NET

27.2.5.1.1. Introduction

All interaction between a .NET application and the MySQL server is routed through a MySqlConnection object. Before your application can interact with the server, a MySqlConnection object must be instanced, configured, and opened.

Even when using the MySqlHelper class, a MySqlConnection object is created by the helper class.

In this section, we will describe how to connect to MySQL using the MySqlConnection object.

27.2.5.1.2. Creating a Connection String

The MySqlConnection object is configured using a connection string. A connection string contains sever key/value pairs, separated by semicolons. Each key/value pair is joined with an equals sign.

The following is a sample connection string:

    Server=127.0.0.1;Uid=root;Pwd=12345;Database=test;
    

In this example, the MySqlConnection object is configured to connect to a MySQL server at 127.0.0.1, with a username of root and a password of 12345. The default database for all statements will be the test database.

The following options are typically used (a full list of options is available in the API documentation for Section 27.2.3.3.3, “ConnectionString”):

  • Server: The name or network address of the instance of MySQL to which to connect. The default is localhost. Aliases include host, Data Source, DataSource, Address, Addr and Network Address.

  • Uid: The MySQL user account to use when connecting. Aliases include User Id, Username and User name.

  • Pwd: The password for the MySQL account being used. Alias Password can also be used.

  • Database: The default database that all statements are applied to. Default is mysql. Alias Initial Catalog can also be used.

  • Port: The port MySQL is using to listen for connections. Default is 3306. Specify -1 for this value to use a named-pipe connection.

27.2.5.1.3. Opening a Connection

Once you have created a connection string it can be used to open a connection to the MySQL server.

The following code is used to create a MySqlConnection object, assign the connection string, and open the connection.

Visual Basic Example

Dim conn As New MySql.Data.MySqlClient.MySqlConnection
Dim myConnectionString as String

myConnectionString = "server=127.0.0.1;" _
            & "uid=root;" _
            & "pwd=12345;" _
            & "database=test;"

Try
  conn.ConnectionString = myConnectionString
  conn.Open()

Catch ex As MySql.Data.MySqlClient.MySqlException
  MessageBox.Show(ex.Message)
End Try
  

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
string myConnectionString;
    
myConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";
  
try
{
    conn = new MySql.Data.MySqlClient.MySqlConnection();
    conn.ConnectionString = myConnectionString;
    conn.Open();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show(ex.Message);
}

You can also pass the connection string to the constructor of the MySqlConnection class:

Visual Basic Example

Dim myConnectionString as String

myConnectionString = "server=127.0.0.1;" _
              & "uid=root;" _
              & "pwd=12345;" _
              & "database=test;" 

Try
    Dim conn As New MySql.Data.MySqlClient.MySqlConnection(myConnectionString)
    conn.Open()
Catch ex As MySql.Data.MySqlClient.MySqlException
   MessageBox.Show(ex.Message)
End Try
  

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
string myConnectionString;

myConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

try
{
    conn = new MySql.Data.MySqlClient.MySqlConnection(myConnectionString);
    conn.Open();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show(ex.Message);
}

Once the connection is open it can be used by the other Connector/NET classes to communicate with the MySQL server.

27.2.5.1.4. Handling Connection Errors

Because connecting to an external server is unpredictable, it is important to add error handling to your .NET application. When there is an error connecting, the MySqlConnection class will return a MySqlException object. This object has two properties that are of interest when handling errors:

  • Message: A message that describes the current exception.

  • Number: The MySQL error number.

When handling errors, you can your application's response based on the error number. The two most common error numbers when connecting are as follows:

  • 0: Cannot connect to server.

  • 1045: Invalid username and/or password.

The following code shows how to adapt the application's response based on the actual error:

Visual Basic Example

Dim myConnectionString as String

myConnectionString = "server=127.0.0.1;" _
          & "uid=root;" _
          & "pwd=12345;" _
          & "database=test;" 

Try
    Dim conn As New MySql.Data.MySqlClient.MySqlConnection(myConnectionString)
    conn.Open()
Catch ex As MySql.Data.MySqlClient.MySqlException
    Select Case ex.Number
        Case 0
            MessageBox.Show("Cannot connect to server. Contact administrator")
        Case 1045
            MessageBox.Show("Invalid username/password, please try again")
    End Select
End Try
  

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
string myConnectionString;

myConnectionString = "server=127.0.0.1;uid=root;" +  
    "pwd=12345;database=test;";

try
{
    conn = new MySql.Data.MySqlClient.MySqlConnection(myConnectionString);
    conn.Open();
}
    catch (MySql.Data.MySqlClient.MySqlException ex)
{
    switch (ex.Number)
    {
        case 0:
            MessageBox.Show("Cannot connect to server.  Contact administrator");
        case 1045:
            MessageBox.Show("Invalid username/password, please try again");
    }
}
  

Important

Note that if you are using multilanguage databases you must specify the character set in the connection string. If you do not specify the character set, the connection defaults to the latin1 charset. You can specify the character set as part of the connection string, for example:

MySqlConnection myConnection = new MySqlConnection("server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;Charset=latin1;");

27.2.5.2. Using the Connector/NET with Prepared Statements

27.2.5.2.1. Introduction

As of MySQL 4.1, it is possible to use prepared statements with Connector/NET. Use of prepared statements can provide significant performance improvements on queries that are executed more than once.

Prepared execution is faster than direct execution for statements executed more than once, primarily because the query is parsed only once. In the case of direct execution, the query is parsed every time it is executed. Prepared execution also can provide a reduction of network traffic because for each execution of the prepared statement, it is necessary only to send the data for the parameters.

Another advantage of prepared statements is that it uses a binary protocol that makes data transfer between client and server more efficient.

27.2.5.2.2. Preparing Statements in Connector/NET

To prepare a statement, create a command object and set the .CommandText property to your query.

After entering your statement, call the .Prepare method of the MySqlCommand object. After the statement is prepared, add parameters for each of the dynamic elements in the query.

After you enter your query and enter parameters, execute the statement using the .ExecuteNonQuery(), .ExecuteScalar(), or .ExecuteReader methods.

For subsequent executions, you need only modify the values of the parameters and call the execute method again, there is no need to set the .CommandText property or redefine the parameters.

Visual Basic Example

Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand
  
conn.ConnectionString = strConnection

Try
   conn.Open()
   cmd.Connection = conn
 
   cmd.CommandText = "INSERT INTO myTable VALUES(NULL, @number, @text)"
   cmd.Prepare()

   cmd.Parameters.Add("@number", 1)
   cmd.Parameters.Add("@text", "One")

   For i = 1 To 1000
       cmd.Parameters["@number"].Value = i
       cmd.Parameters["@text"].Value = "A string value"

       cmd.ExecuteNonQuery()
     Next 
Catch ex As MySqlException
    MessageBox.Show("Error " & ex.Number & " has occurred: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
  

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;
  
conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();

conn.ConnectionString = strConnection;

try
{
    conn.Open();
    cmd.Connection = conn;

    cmd.CommandText = "INSERT INTO myTable VALUES(NULL, @number, @text)";
    cmd.Prepare();

    cmd.Parameters.Add("@number", 1);
    cmd.Parameters.Add("@text", "One");

    for (int i=1; i <= 1000; i++)
    {
        cmd.Parameters["@number"].Value = i;
        cmd.Parameters["@text"].Value = "A string value";

        cmd.ExecuteNonQuery();
    }
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
        "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}

27.2.5.3. Accessing Stored Procedures with Connector/NET

27.2.5.3.1. Introduction

With the release of MySQL version 5 the MySQL server now supports stored procedures with the SQL 2003 stored procedure syntax.

A stored procedure is a set of SQL statements that can be stored in the server. Once this has been done, clients don't need to keep reissuing the individual statements but can refer to the stored procedure instead.

Stored procedures can be particularly useful in situations such as the following:

  • When multiple client applications are written in different languages or work on different platforms, but need to perform the same database operations.

  • When security is paramount. Banks, for example, use stored procedures for all common operations. This provides a consistent and secure environment, and procedures can ensure that each operation is properly logged. In such a setup, applications and users would not get any access to the database tables directly, but can only execute specific stored procedures.

Connector/NET supports the calling of stored procedures through the MySqlCommand object. Data can be passed in and our of a MySQL stored procedure through use of the MySqlCommand.Parameters collection.

Note

When you call a stored procedure, the command object makes an additional SELECT call to determine the parameters of the stored procedure. You must ensure that the user calling the procedure has the SELECT privilege on the mysql.proc table to enable them to verify the parameters. Failure to do this will result in an error when calling the procedure.

This section will not provide in-depth information on creating Stored Procedures. For such information, please refer to http://dev.mysql.com/doc/mysql/en/stored-procedures.html.

A sample application demonstrating how to use stored procedures with Connector/NET can be found in the Samples directory of your Connector/NET installation.

27.2.5.3.2. Creating Stored Procedures from Connector/NET

Stored procedures in MySQL can be created using a variety of tools. First, stored procedures can be created using the mysql command-line client. Second, stored procedures can be created using the MySQL Query Browser GUI client. Finally, stored procedures can be created using the .ExecuteNonQuery method of the MySqlCommand object:

Visual Basic Example

Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand

conn.ConnectionString = "server=127.0.0.1;" _
    & "uid=root;" _
    & "pwd=12345;" _
    & "database=test"

Try
    conn.Open()
    cmd.Connection = conn

    cmd.CommandText = "CREATE PROCEDURE add_emp(" _
        & "IN fname VARCHAR(20), IN lname VARCHAR(20), IN bday DATETIME, OUT empno INT) " _
        & "BEGIN INSERT INTO emp(first_name, last_name, birthdate) " _
        & "VALUES(fname, lname, DATE(bday)); SET empno = LAST_INSERT_ID(); END"
 
    cmd.ExecuteNonQuery()
Catch ex As MySqlException
    MessageBox.Show("Error " & ex.Number & " has occurred: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

try
{
    conn.Open();
    cmd.Connection = conn;

    cmd.CommandText = "CREATE PROCEDURE add_emp(" +
        "IN fname VARCHAR(20), IN lname VARCHAR(20), IN bday DATETIME, OUT empno INT) " +
        "BEGIN INSERT INTO emp(first_name, last_name, birthdate) " +
        "VALUES(fname, lname, DATE(bday)); SET empno = LAST_INSERT_ID(); END";

    cmd.ExecuteNonQuery();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
    "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}

It should be noted that, unlike the command-line and GUI clients, you are not required to specify a special delimiter when creating stored procedures in Connector/NET.

27.2.5.3.3. Calling a Stored Procedure from Connector/NET

To call a stored procedure using Connector/NET, create a MySqlCommand object and pass the stored procedure name as the .CommandText property. Set the .CommandType property to CommandType.StoredProcedure.

After the stored procedure is named, create one MySqlCommand parameter for every parameter in the stored procedure. IN parameters are defined with the parameter name and the object containing the value, OUT parameters are defined with the parameter name and the datatype that is expected to be returned. All parameters need the parameter direction defined.

After defining parameters, call the stored procedure by using the MySqlCommand.ExecuteNonQuery() method:

Visual Basic Example

Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand

conn.ConnectionString = "server=127.0.0.1;" _
    & "uid=root;" _
    & "pwd=12345;" _
    & "database=test"

Try
    conn.Open()
    cmd.Connection = conn

    cmd.CommandText = "add_emp"
    cmd.CommandType = CommandType.StoredProcedure

    cmd.Parameters.Add("@lname", 'Jones')
    cmd.Parameters["@lname"].Direction = ParameterDirection.Input

    cmd.Parameters.Add("@fname", 'Tom')
    cmd.Parameters["@fname"].Direction = ParameterDirection.Input

    cmd.Parameters.Add("@bday", #12/13/1977 2:17:36 PM#)
    cmd.Parameters["@bday"].Direction = ParameterDirection.Input

    cmd.Parameters.Add("@empno", MySqlDbType.Int32)
    cmd.Parameters["@empno"].Direction = ParameterDirection.Output

    cmd.ExecuteNonQuery()

    MessageBox.Show(cmd.Parameters["@empno"].Value)
Catch ex As MySqlException
    MessageBox.Show("Error " & ex.Number & " has occurred: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

try
{
    conn.Open();
    cmd.Connection = conn;

    cmd.CommandText = "add_emp";
    cmd.CommandType = CommandType.StoredProcedure;

    cmd.Parameters.Add("@lname", "Jones");
    cmd.Parameters["@lname"].Direction = ParameterDirection.Input;

    cmd.Parameters.Add("@fname", "Tom");
    cmd.Parameters["@fname"].Direction = ParameterDirection.Input;

    cmd.Parameters.Add("@bday", DateTime.Parse("12/13/1977 2:17:36 PM"));
    cmd.Parameters["@bday"].Direction = ParameterDirection.Input;

    cmd.Parameters.Add("@empno", MySqlDbType.Int32);
    cmd.Parameters["@empno"].Direction = ParameterDirection.Output;

    cmd.ExecuteNonQuery();

    MessageBox.Show(cmd.Parameters["@empno"].Value);
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
      "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}

Once the stored procedure is called, the values of output parameters can be retrieved by using the .Value property of the MySqlConnector.Parameters collection.

27.2.5.4. Handling BLOB Data With Connector/NET

27.2.5.4.1. Introduction

One common use for MySQL is the storage of binary data in BLOB columns. MySQL supports four different BLOB datatypes: TINYBLOB, BLOB, MEDIUMBLOB, and LONGBLOB.

Data stored in a BLOB column can be accessed using Connector/NET and manipulated using client-side code. There are no special requirements for using Connector/NET with BLOB data.

Simple code examples will be presented within this section, and a full sample application can be found in the Samples directory of the Connector/NET installation.

27.2.5.4.2. Preparing the MySQL Server

The first step is using MySQL with BLOB data is to configure the server. Let's start by creating a table to be accessed. In my file tables, I usually have four columns: an AUTO_INCREMENT column of appropriate size (UNSIGNED SMALLINT) to serve as a primary key to identify the file, a VARCHAR column that stores the filename, an UNSIGNED MEDIUMINT column that stores the size of the file, and a MEDIUMBLOB column that stores the file itself. For this example, I will use the following table definition:

CREATE TABLE file(
file_id SMALLINT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY,
file_name VARCHAR(64) NOT NULL,
file_size MEDIUMINT UNSIGNED NOT NULL,
file MEDIUMBLOB NOT NULL);

After creating a table, you may need to modify the max_allowed_packet system variable. This variable determines how large of a packet (i.e. a single row) can be sent to the MySQL server. By default, the server will only accept a maximum size of 1 meg from our client application. If you do not intend to exceed 1 meg, this should be fine. If you do intend to exceed 1 meg in your file transfers, this number has to be increased.

The max_allowed_packet option can be modified using MySQL Administrator's Startup Variables screen. Adjust the Maximum allowed option in the Memory section of the Networking tab to an appropriate setting. After adjusting the value, click the Apply Changes button and restart the server using the Service Control screen of MySQL Administrator. You can also adjust this value directly in the my.cnf file (add a line that reads max_allowed_packet=xxM), or use the SET max_allowed_packet=xxM; syntax from within MySQL.

Try to be conservative when setting max_allowed_packet, as transfers of BLOB data can take some time to complete. Try to set a value that will be adequate for your intended use and increase the value if necessary.

27.2.5.4.3. Writing a File to the Database

To write a file to a database we need to convert the file to a byte array, then use the byte array as a parameter to an INSERT query.

The following code opens a file using a FileStream object, reads it into a byte array, and inserts it into the file table:

Visual Basic Example

Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand

Dim SQL As String

Dim FileSize As UInt32
Dim rawData() As Byte
Dim fs As FileStream

conn.ConnectionString = "server=127.0.0.1;" _
    & "uid=root;" _
    & "pwd=12345;" _
    & "database=test"

Try
    fs = New FileStream("c:\image.png", FileMode.Open, FileAccess.Read)
    FileSize = fs.Length
    
    rawData = New Byte(FileSize) {}
    fs.Read(rawData, 0, FileSize)
    fs.Close()
    
    conn.Open()
    
    SQL = "INSERT INTO file VALUES(NULL, @FileName, @FileSize, @File)"
    
    cmd.Connection = conn
    cmd.CommandText = SQL
    cmd.Parameters.Add("@FileName", strFileName)
    cmd.Parameters.Add("@FileSize", FileSize)
    cmd.Parameters.Add("@File", rawData)
    
    cmd.ExecuteNonQuery()
    
    MessageBox.Show("File Inserted into database successfully!", _
    "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk)
    
    conn.Close()
Catch ex As Exception
    MessageBox.Show("There was an error: " & ex.Message, "Error", _
        MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
  

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();

string SQL;
UInt32 FileSize;
byte[] rawData;
FileStream fs;

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

try
{
    fs = new FileStream(@"c:\image.png", FileMode.Open, FileAccess.Read);
    FileSize = fs.Length;

    rawData = new byte[FileSize];
    fs.Read(rawData, 0, FileSize);
    fs.Close();

    conn.Open();

    SQL = "INSERT INTO file VALUES(NULL, @FileName, @FileSize, @File)";

    cmd.Connection = conn;
    cmd.CommandText = SQL;
    cmd.Parameters.Add("@FileName", strFileName);
    cmd.Parameters.Add("@FileSize", FileSize);
    cmd.Parameters.Add("@File", rawData);

    cmd.ExecuteNonQuery();

    MessageBox.Show("File Inserted into database successfully!",
        "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);

    conn.Close();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
        "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
 

The Read method of the FileStream object is used to load the file into a byte array which is sized according to the Length property of the FileStream object.

After assigning the byte array as a parameter of the MySqlCommand object, the ExecuteNonQuery method is called and the BLOB is inserted into the file table.

27.2.5.4.4. Reading a BLOB from the Database to a File on Disk

Once a file is loaded into the file table, we can use the MySqlDataReader class to retrieve it.

The following code retrieves a row from the file table, then loads the data into a FileStream object to be written to disk:

Visual Basic Example

Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand
Dim myData As MySqlDataReader
Dim SQL As String
Dim rawData() As Byte
Dim FileSize As UInt32
Dim fs As FileStream

conn.ConnectionString = "server=127.0.0.1;" _
    & "uid=root;" _
    & "pwd=12345;" _
    & "database=test"

SQL = "SELECT file_name, file_size, file FROM file"

Try
    conn.Open()
    
    cmd.Connection = conn
    cmd.CommandText = SQL
    
    myData = cmd.ExecuteReader
    
    If Not myData.HasRows Then Throw New Exception("There are no BLOBs to save")
    
    myData.Read()
    
    FileSize = myData.GetUInt32(myData.GetOrdinal("file_size"))
    rawData = New Byte(FileSize) {}
    
    myData.GetBytes(myData.GetOrdinal("file"), 0, rawData, 0, FileSize)
    
    fs = New FileStream("C:\newfile.png", FileMode.OpenOrCreate, FileAccess.Write)
    fs.Write(rawData, 0, FileSize)
    fs.Close()
    
    MessageBox.Show("File successfully written to disk!", "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk)
    
    myData.Close()
    conn.Close()
Catch ex As Exception
    MessageBox.Show("There was an error: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
  

C# Example

MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;
MySql.Data.MySqlClient.MySqlDataReader myData;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();

string SQL;
UInt32 FileSize;
byte[] rawData;
FileStream fs;

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

SQL = "SELECT file_name, file_size, file FROM file";

try
{
    conn.Open();

    cmd.Connection = conn;
    cmd.CommandText = SQL;

    myData = cmd.ExecuteReader();

    if (! myData.HasRows)
        throw new Exception("There are no BLOBs to save");

    myData.Read();

    FileSize = myData.GetUInt32(myData.GetOrdinal("file_size"));
    rawData = new byte[FileSize];

    myData.GetBytes(myData.GetOrdinal("file"), 0, rawData, 0, FileSize);

    fs = new FileStream(@"C:\newfile.png", FileMode.OpenOrCreate, FileAccess.Write);
    fs.Write(rawData, 0, FileSize);
    fs.Close();

    MessageBox.Show("File successfully written to disk!",
        "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);

    myData.Close();
    conn.Close();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
        "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
 

After connecting, the contents of the file table are loaded into a MySqlDataReader object. The GetBytes method of the MySqlDataReader is used to load the BLOB into a byte array, which is then written to disk using a FileStream object.

The GetOrdinal method of the MySqlDataReader can be used to determine the integer index of a named column. Use of the GetOrdinal method prevents errors if the column order of the SELECT query is changed.

27.2.5.5. Using Connector/NET with Crystal Reports

27.2.5.5.1. Introduction

Crystal Reports is a common tool used by Windows application developers to perform reporting and document generation. In this section we will show how to use Crystal Reports XI with MySQL and Connector/NET.

27.2.5.5.2. Creating a Data Source

When creating a report in Crystal Reports there are two options for accessing the MySQL data while designing your report.

The first option is to use Connector/ODBC as an ADO data source when designing your report. You will be able to browse your database and choose tables and fields using drag and drop to build your report. The disadvantage of this approach is that additional work must be performed within your application to produce a data set that matches the one expected by your report.

The second option is to create a data set in VB.NET and save it as XML. This XML file can then be used to design a report. This works quite well when displaying the report in your application, but is less versatile at design time because you must choose all relevant columns when creating the data set. If you forget a column you must re-create the data set before the column can be added to the report.

The following code can be used to create a data set from a query and write it to disk:

Visual Basic Example

Dim myData As New DataSet
Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand
Dim myAdapter As New MySqlDataAdapter

conn.ConnectionString = "server=127.0.0.1;" _
    & "uid=root;" _
    & "pwd=12345;" _
    & "database=world"

Try
    conn.Open()
    cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " _ 
        & "country.name, country.population, country.continent " _
        & "FROM country, city ORDER BY country.continent, country.name"
    cmd.Connection = conn
    
    myAdapter.SelectCommand = cmd
    myAdapter.Fill(myData)
    
    myData.WriteXml("C:\dataset.xml", XmlWriteMode.WriteSchema)
Catch ex As Exception
    MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
 

C# Example

DataSet myData = new DataSet();
MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;
MySql.Data.MySqlClient.MySqlDataAdapter myAdapter;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();
myAdapter = new MySql.Data.MySqlClient.MySqlDataAdapter();

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
  "pwd=12345;database=test;";
  
try
{
  cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " +
  "country.name, country.population, country.continent " +
  "FROM country, city ORDER BY country.continent, country.name";
  cmd.Connection = conn;
  
  myAdapter.SelectCommand = cmd;
  myAdapter.Fill(myData);
  
  myData.WriteXml(@"C:\dataset.xml", XmlWriteMode.WriteSchema);
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
  MessageBox.Show(ex.Message, "Report could not be created",
  MessageBoxButtons.OK, MessageBoxIcon.Error);
}

The resulting XML file can be used as an ADO.NET XML datasource when designing your report.

If you choose to design your reports using Connector/ODBC, it can be downloaded from dev.mysql.com.

27.2.5.5.3. Creating the Report

For most purposes the Standard Report wizard should help with the initial creation of a report. To start the wizard, open Crystal Reports and choose the New > Standard Report option from the File menu.

The wizard will first prompt you for a data source. If you are using Connector/ODBC as your data source, use the OLEDB provider for ODBC option from the OLE DB (ADO) tree instead of the ODBC (RDO) tree when choosing a data source. If using a saved data set, choose the ADO.NET (XML) option and browse to your saved data set.

The remainder of the report creation process is done automatically by the wizard.

After the report is created, choose the Report Options... entry of the File menu. Un-check the Save Data With Report option. This prevents saved data from interfering with the loading of data within our application.

27.2.5.5.4. Displaying the Report

To display a report we first populate a data set with the data needed for the report, then load the report and bind it to the data set. Finally we pass the report to the crViewer control for display to the user.

The following references are needed in a project that displays a report:

  • CrytalDecisions.CrystalReports.Engine

  • CrystalDecisions.ReportSource

  • CrystalDecisions.Shared

  • CrystalDecisions.Windows.Forms

The following code assumes that you created your report using a data set saved using the code shown in Section 27.2.5.5.2, “Creating a Data Source”, and have a crViewer control on your form named myViewer.

Visual Basic Example

Imports CrystalDecisions.CrystalReports.Engine
Imports System.Data
Imports MySql.Data.MySqlClient

Dim myReport As New ReportDocument
Dim myData As New DataSet
Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand
Dim myAdapter As New MySqlDataAdapter

conn.ConnectionString = _
    "server=127.0.0.1;" _
    & "uid=root;" _
    & "pwd=12345;" _
    & "database=test"

Try
    conn.Open()
    
    cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " _ 
        & "country.name, country.population, country.continent " _
        & "FROM country, city ORDER BY country.continent, country.name"
    cmd.Connection = conn
    
    myAdapter.SelectCommand = cmd
    myAdapter.Fill(myData)
    
    myReport.Load(".\world_report.rpt")
    myReport.SetDataSource(myData)
    myViewer.ReportSource = myReport
Catch ex As Exception
    MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try

C# Example

using CrystalDecisions.CrystalReports.Engine;
using System.Data;
using MySql.Data.MySqlClient;

ReportDocument myReport = new ReportDocument();
DataSet myData = new DataSet();
MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;
MySql.Data.MySqlClient.MySqlDataAdapter myAdapter;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();
myAdapter = new MySql.Data.MySqlClient.MySqlDataAdapter();

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

try
{
    cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " +
        "country.name, country.population, country.continent " +
        "FROM country, city ORDER BY country.continent, country.name";
    cmd.Connection = conn;

    myAdapter.SelectCommand = cmd;
    myAdapter.Fill(myData);

    myReport.Load(@".\world_report.rpt");
    myReport.SetDataSource(myData);
    myViewer.ReportSource = myReport;
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show(ex.Message, "Report could not be created",
        MessageBoxButtons.OK, MessageBoxIcon.Error);
}

A new data set it generated using the same query used to generate the previously saved data set. Once the data set is filled, a ReportDocument is used to load the report file and bind it to the data set. The ReportDocument is the passed as the ReportSource of the crViewer.

This same approach is taken when a report is created from a single table using Connector/ODBC. The data set replaces the table used in the report and the report is displayed properly.

When a report is created from multiple tables using Connector/ODBC, a data set with multiple tables must be created in our application. This allows each table in the report data source to be replaced with a report in the data set.

We populate a data set with multiple tables by providing multiple SELECT statements in our MySqlCommand object. These SELECT statements are based on the SQL query shown in Crystal Reports in the Database menu's Show SQL Query option. Assume the following query:

SELECT `country`.`Name`, `country`.`Continent`, `country`.`Population`, `city`.`Name`, `city`.`Population`
FROM `world`.`country` `country` LEFT OUTER JOIN `world`.`city` `city` ON `country`.`Code`=`city`.`CountryCode`
ORDER BY `country`.`Continent`, `country`.`Name`, `city`.`Name`

This query is converted to two SELECT queries and displayed with the following code:

Visual Basic Example

Imports CrystalDecisions.CrystalReports.Engine
Imports System.Data
Imports MySql.Data.MySqlClient

Dim myReport As New ReportDocument
Dim myData As New DataSet
Dim conn As New MySqlConnection
Dim cmd As New MySqlCommand
Dim myAdapter As New MySqlDataAdapter

conn.ConnectionString = "server=127.0.0.1;" _
    & "uid=root;" _
    & "pwd=12345;" _
    & "database=world"

Try
    conn.Open()
    cmd.CommandText = "SELECT name, population, countrycode FROM city ORDER BY countrycode, name; " _
        & "SELECT name, population, code, continent FROM country ORDER BY continent, name"
    cmd.Connection = conn
    
    myAdapter.SelectCommand = cmd
    myAdapter.Fill(myData)
    
    myReport.Load(".\world_report.rpt")
    myReport.Database.Tables(0).SetDataSource(myData.Tables(0))
    myReport.Database.Tables(1).SetDataSource(myData.Tables(1))
    myViewer.ReportSource = myReport
Catch ex As Exception
    MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try

C# Example

using CrystalDecisions.CrystalReports.Engine;
using System.Data;
using MySql.Data.MySqlClient;

ReportDocument myReport = new ReportDocument();
DataSet myData = new DataSet();
MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;
MySql.Data.MySqlClient.MySqlDataAdapter myAdapter;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();
myAdapter = new MySql.Data.MySqlClient.MySqlDataAdapter();

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

try
{
    cmd.CommandText = "SELECT name, population, countrycode FROM city ORDER " +
        "BY countrycode, name; SELECT name, population, code, continent FROM " +
        "country ORDER BY continent, name";
    cmd.Connection = conn;

    myAdapter.SelectCommand = cmd;
    myAdapter.Fill(myData);

    myReport.Load(@".\world_report.rpt");
    myReport.Database.Tables(0).SetDataSource(myData.Tables(0));
    myReport.Database.Tables(1).SetDataSource(myData.Tables(1));
    myViewer.ReportSource = myReport;
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show(ex.Message, "Report could not be created",
        MessageBoxButtons.OK, MessageBoxIcon.Error);
}  
 

It is important to order the SELECT queries in alphabetical order, as this is the order the report will expect its source tables to be in. One SetDataSource statement is needed for each table in the report.

This approach can cause performance problems because Crystal Reports must bind the tables together on the client-side, which will be slower than using a pre-saved data set.

27.2.5.6. Handling Date and Time Information in Connector/NET

27.2.5.6.1. Introduction

MySQL and the .NET languages handle date and time information differently, with MySQL allowing dates that cannot be represented by a .NET data type, such as '0000-00-00 00:00:00'. These differences can cause problems if not properly handled.

In this section we will demonstrate how to properly handle date and time information when using Connector/NET.

27.2.5.6.2. Problems when Using Invalid Dates

The differences in date handling can cause problems for developers who use invalid dates. Invalid MySQL dates cannot be loaded into native .NET DateTime objects, including NULL dates.

Because of this issue, .NET DataSet objects cannot be populated by the Fill method of the MySqlDataAdapter class as invalid dates will cause a System.ArgumentOutOfRangeException exception to occur.

27.2.5.6.3. Restricting Invalid Dates

The best solution to the date problem is to restrict users from entering invalid dates. This can be done on either the client or the server side.

Restricting invalid dates on the client side is as simple as always using the .NET DateTime class to handle dates. The DateTime class will only allow valid dates, ensuring that the values in your database are also valid. The disadvantage of this is that it is not useful in a mixed environment where .NET and non .NET code are used to manipulate the database, as each application must perform its own date validation.

Users of MySQL 5.0.2 and higher can use the new traditional SQL mode to restrict invalid date values. For information on using the traditional SQL mode, see Section 5.1.7, “SQL Modes”.

27.2.5.6.4. Handling Invalid Dates

Although it is strongly recommended that you avoid the use of invalid dates within your .NET application, it is possible to use invalid dates by means of the MySqlDateTime datatype.

The MySqlDateTime datatype supports the same date values that are supported by the MySQL server. The default behavior of Connector/NET is to return a .NET DateTime object for valid date values, and return an error for invalid dates. This default can be modified to cause Connector/NET to return MySqlDateTime objects for invalid dates.

To instruct Connector/NET to return a MySqlDateTime object for invalid dates, add the following line to your connection string:

  Allow Zero Datetime=True
  

Please note that the use of the MySqlDateTime class can still be problematic. The following are some known issues:

  1. Data binding for invalid dates can still cause errors (zero dates like 0000-00-00 do not seem to have this problem).

  2. The ToString method return a date formatted in the standard MySQL format (for example, 2005-02-23 08:50:25). This differs from the ToString behavior of the .NET DateTime class.

  3. The MySqlDateTime class supports NULL dates, while the .NET DateTime class does not. This can cause errors when trying to convert a MySQLDateTime to a DateTime if you do not check for NULL first.

Because of the known issues, the best recommendation is still to use only valid dates in your application.

27.2.5.6.5. Handling NULL Dates

The .NET DateTime datatype cannot handle NULL values. As such, when assigning values from a query to a DateTime variable, you must first check whether the value is in fact NULL.

When using a MySqlDataReader, use the .IsDBNull method to check whether a value is NULL before making the assignment:

Visual Basic Example

If Not myReader.IsDBNull(myReader.GetOrdinal("mytime")) Then
    myTime = myReader.GetDateTime(myReader.GetOrdinal("mytime"))
Else
    myTime = DateTime.MinValue
End If
  

C# Example

if (! myReader.IsDBNull(myReader.GetOrdinal("mytime")))
    myTime = myReader.GetDateTime(myReader.GetOrdinal("mytime"));
else
    myTime = DateTime.MinValue;
  

NULL values will work in a data set and can be bound to form controls without special handling.

27.2.5.7. Frequently Asked Questions

The following details a number of frequently asked questions about Connector/NET.

Questions

  • 28.2.5.7.1: How do I obtain the value of an auto-incremented column?

Questions and Answers

28.2.5.7.1: How do I obtain the value of an auto-incremented column?

When using the commandBuilder you should make sure that you set the ReturnGeneratedIdentifiers property to true.

Then, you can use an active view on a table to access the updated ID. For example:

				conn = new MySql.Data.MySqlClient.MySqlConnection();
				cmd = new MySql.Data.MySqlClient.MySqlCommand();
				da = new MySql.Data.MySqlClient.MySqlDataAdapter();
				cmdBuilder = new MySql.Data.MySqlClient.MySqlCommandBuilder();
				SystemDataDataSet = new System.Data.DataSet();
				SystemDataDataView = new System.Data.DataView();
...
        cmd.Connection = conn;
        cmd.CommandText = "SELECT * FROM contacts";
			  da.SelectCommand = cmd;
        da.Fill(SystemDataDataSet, "contacts");
				cmdBuilder.DataAdapter = da;
        cmdBuilder.ReturnGeneratedIdentifiers = true;
        cmdBuilder.DataAdapter.SelectCommand.CommandText = "SELECT * FROM contacts";
				cmdBuilder.RefreshSchema();

        SystemDataDataView = SystemDataDataSet.Tables["contacts"].DefaultView;

				SystemDataDataRow = SystemDataDataView.Table.NewRow();
        SystemDataDataRow["status"] = 1;
 
        SystemDataDataView.Table.Rows.Add(SystemDataDataRow);
        da.Update(SystemDataDataSet, "contacts");
        System.Console.WriteLine("ID after update: "  + SystemDataDataRow["id"]);
  

The SystemDataDataRow object in this instance provides the interface to the updated auto-increment value in the id column.

27.2.6. Connector/NET Support

The developers of Connector/NET greatly value the input of our users in the software development process. If you find Connector/NET lacking some feature important to you, or if you discover a bug and need to file a bug report, please use the instructions in Section 1.7, “How to Report Bugs or Problems”.

27.2.6.1. Connector/NET Community Support

27.2.6.2. How to report Connector/NET Problems or Bugs

If you encounter difficulties or problems with Connector/NET, contact the Connector/NET community Section 27.2.6.1, “Connector/NET Community Support”.

You should first try to execute the same SQL statements and commands from the mysql client program or from admndemo. This helps you determine whether the error is in Connector/NET or MySQL.

If reporting a problem, you should ideally include the following information with the email:

  • Operating system and version

  • Connector/NET version

  • MySQL server version

  • Copies of error messages or other unexpected output

  • Simple reproducible sample

Remember that the more information you can supply to us, the more likely it is that we can fix the problem.

If you believe the problem to be a bug, then you must report the bug through http://bugs.mysql.com/.

27.2.6.3. Connector/NET Change History

The Connector/NET Change History (Changelog) is located with the main Changelog for MySQL. See Section E.4, “MySQL Connector/NET Change History”.

27.3. MySQL Visual Studio Plugin

The MySQL Visual Studio Plugin is a DDEX provider; a plug-in for Visual Studio 2005 that allows developers to maintain database structures, and supports built-in data-driven application development tools.

The current version of the MySQL Visual Studio Plugin includes only database maintenance tools. Data-driven application development tools are not supported.

The MySQL DDEX Provider operates as a standard extension to the Visual Studio Data Designer functionality available through the Server Explorer menu of Visual Studio 2005, and enables developers to create database objects and data within a MySQL database.

The MySQL Visual Studio Plugin is designed to work with MySQL version 5.0, but is also compatible with MySQL 4.1.1 and provides limited compatibility with MySQL 5.1.

27.3.1. Installing the MySQL Visual Studio Plugin

The MySQL Visual Studio Plugin requires one of Visual Studio 2005 Standard, Professional or Team Developer Edition to be installed. Other editions of Visual Studio 2005 are not supported.

Note

Starting with Connector/NET 5.1.2, the Visual Studio Plugin is included in the installation. If you have installed Connector/NET 5.1.2, then you do not need to separately install the Visual Studio Plugin.

Here is the list of components that should already be installed before starting the installation of the MySQL Visual Studio Plugin:

  • Visual Studio 2005 Standard, Professional or Team Developer Edition.

  • MySQL Server 4.1.1 or later (either installed on the same machine, or a separate server).

  • MySQL Connector/NET 5.0.

Note

When installing Connector/NET you must ensure that the connector is installed into the Global Assembly Cache (GAC). The Connector/NET installer handles this for you automatically, but in a custom installation the option may have been disabled.

The user used to connect to the MySQL server must have the following privileges to use the functionality provided by the MySQL Visual Studio Plugin:

  • The SELECT privilege for the INFORMATION_SCHEMA database.

  • The EXECUTE privilege for the SHOW CREATE TABLE statement.

  • The SELECT privilege for the mysql.proc table (required for operations with stored procedures and functions).

  • The SELECT privilege for the mysql.func table (required for operations with User Defined Functions (UDF)).

  • The EXECUTE privilege for the SHOW ENGINE STATUS statement (required for retrieving extended error information).

  • Appropriate privileges for performed operations (e.g. the SELECT privilege is required to browse data from a table etc.).

The MySQL Visual Studio Plugin is delivered as a MSI package that can be used to install, uninstall or reinstall the Provider. If you are not using Windows XP or Windows Server 2003 you upgrade the Windows Installer system to the latest version (see http://support.microsoft.com/default.aspx?scid=kb;EN-US;292539 for details).

The MSI-package is named MySQL.VisualStudio.msi. To install the MySQL Visual Studio Plugin, right click on the MSI file and select Install. The installation process is as follow:

  1. The standard Welcome dialog is opened. Click Next to continue installation.

  2. The License agreement (GNU GPL) window is opened. Accept the agreement and click Next to continue.

  3. The destination folder choice dialog is opened. Here you can point out the folder where the MySQL Visual Studio Plugin will be installed. The default destination folder is %ProgramFilesDir%\MySQL\MySQL DDEX Data Provider, where %ProgramFilesDir% is the Program Files folder of the installation machine. After choosing the destination folder, click Next to continue.

  4. The installer will ask to confirm that installation. Click Install to start installation process.

  5. The installation will now take place. At the end of this step the Visual Studio command table is rebuilt (this process may take several minutes).

  6. Once installation is complete, click Finish to end the installation process.

To uninstall the MySQL Visual Studio Plugin, you can use either Add/Remove Programs component of the Control Panel or the same MSI-package. Choose the Remove option, and the Provider will be uninstalled automatically.

To repair the Provider, right click the MSI-package and choose the Repair option. The MySQL Visual Studio Plugin will be repaired automatically.

The installation package includes the following files:

  • MySQL.VisualStudio.dll — the MySQL DDEX Provider assembly.

  • MySQL.Data.dll — the assembly containing the MySQL Connector .NET which is used by the Provider.

  • MySql.VisualStudio.dll.config — the configuration file for the MySQL Visual Studio Plugin. This file contains default values for the provider GUI layout.

    Note

    Do not remove this file before the first use of the Provider.

  • Register.reg — the file with registry entries that can be used to register the MySQL DDEX Provider in the case of the manual installation.

  • Install.js — the script used to register the Connector .NET as an ADO.NET data provider in the machine.config file.

  • Release notes.doc — the document with release notes.

To install the Provider manually, copy all files of the installation package in a desired folder, then set the full path to the Provider assembly as a value of the CodeBase entry. For example:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\Packages\{79A115C9-B133-4891-9E7B-242509DAD272}]@="MySql.Data.VisualStudio.MySqlDataProviderPackage"
"InprocServer32"="C:\\WINNT\\system32\\mscoree.dll"
"Class"="MySql.Data.VisualStudio.MySqlDataProviderPackage"
"CodeBase"="C:\\MySqlDdexProvider\\MySql.VisualStudio.dll"

Then import information from the Register.reg file to the registry by clicking of the file. At the confirmation dialog choose Yes. Next you must run the command devenv.exe /setup within a Command Prompt to rebuild the Visual Studio command table.

27.3.2. Creating a connection to the MySQL server

Once the MySQL Visual Studio Plugin is installed, you can use it to create, modify and delete connections to MySQL databases. To create a connection with a MySQL database, perform the following steps:

  1. Start Visual Studio 2005 and open Server Explorer window by choosing the Server Explorer option from the View menu.

  2. Right click on the Data Connections node and choose the Add Connection button.

  3. The Add Connection dialog is opened. Press the Change button to choose MySQL Database as a data source.

  4. Change Data Source dialog is opened. Choose MySQL Database in the list of data sources (or the other option, if MySQL Database is absent), and then choose .NET Framework Data Provider for MySQL in the combo box of data providers.

    Choosing a data source

    Press OK to confirm your choice.

  5. Enter the connection settings: the server host name (for example, localhost if the MySQL server is installed on the local machine), the user name, the password, and the default database schema. Note that you must specify the default schema name to open the connection.

    Setting connection properties
  6. You can also set the port to connect with the MySQL server by pressing the Advanced button. To test a connection with the MySQL server, ser the server host name, the user name, and the password, and press the Test Connection button. If the test fails, check the connection values that you have supplied are correct and that the corresponding user and privileges have been configured on the MySQL server.

  7. After you set all settings and test the connection, press OK. The newly created connection is displayed in Server Explorer. Now you can work with the MySQL server through standard Server Explorer interface.

After a connection is successfully established, all the connection settings are saved. When you next open Visual Studio, the connection to the MySQL server will appear within Server Explorer so that you can re-establish a connection to the MySQL server.

To modify and delete a connection, use the Server Explorer context menu for the corresponding node. You can modify any of the settings just by overwriting the existing values with new ones. Note that a connection should be modified or deleted only if no active editor for it's objects is opened. Otherwise your data could be lost.

27.3.3. Using the MySQL Visual Studio Plugin

To work with a MySQL server using the MySQL Visual Studio Plugin, open the Visual Studio 2005, open the Server Explorer, and select the required connection. The working area of the MySQL Visual Studio Plugin consists of three parts.

DDEX enviroment
  • Database objects (tables, views, stored routines, triggers, and user defined functions) are displayed in the Server Explorer tree. Here you can choose an object and edit its properties and definition.

  • Properties of a selected database object are displayed in the Properties panel. Certain properties can be edited directly within this window.

  • The editor panel provides direct access to the SQL statement and definition of specific objects. Fore example, the SQL statements within a stored procedure definition are shown and edited within this panel.

27.3.3.1. Editing Tables

The Table Editor can be accessed through a mouse action on table-type node of Server Explorer. To create a new table, right click on the Tables node (under the connection node) and choose the Create Table command from a context menu. To modify an existing table, double click on a node of the table you wish to modify, or right click on this node and choose the Alter Table command from a context menu. Either of the commands opens the Table Editor.

Editing a table

The MySQL Visual Studio Plugin Table Editor is implemented in a similar fashion to the standard Query Browser Table Editor, but with minor differences.

The Table Editor consists of the following parts:

  • Columns Editor — for column creation, modification and deletion.

  • Indexes tab — for table/column index management.

  • Foreign Keys tab — for configuration of foreign keys.

  • Column Details tab — used to set advanced column options.

  • Properties window — used to set table properties.

To save changes you have made in the Table Editor, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Ctrl+S. Before changes are saved, a confirmation dialog will be displayed to confirm that you want to update the corresponding object within the MySQL database.

27.3.3.1.1. Column Editor

You can use the Column Editor to set or change the name, data type, default value and other properties of a table column. To set the properties of an individual column, select the column using the mouse. Alternatively, you can move through the grid using Tab and Shift+Tab keys.

  • To set or change the name, data type, default value and comment of a column, select the appropriate cell and edit the desired value.

  • To set or unset flag-type column properties (i.e., primary key, NOT NULL, auto-incremented, flags), check or uncheck the corresponding checkboxes. Note that the available column flags will depend on the columns data type.

  • To reorder columns, index columns or foreign key columns in the Column Editor, select the whole column you wish to reorder by clicking on the selector column at the left of the column grid. Then move the column by using Ctrl+Up (to move the column up) and Ctrl+Down (to move the column down) keys.

  • To delete a column, select it by clicking on the selector column at the left of the column grid, then press the Delete button on a keyboard.

27.3.3.1.2. Indexes tab

Index management is performed via the Indexes tab.

  • To add an index, press the + button and set the properties in the Index Settings groupbox at the right. You can set the index name, index kind, index type and a set of index columns.

  • To remove an index, select the index from the list and press the - button.

  • To change index settings, select the index from the list; detailed information about the index is displayed in the Index Settings panel.

You cannot change a table column to an index column using drag and drop. Instead, you can add new index columns to a table and set their table columns by using the embedded editor within the Indexes tab

27.3.3.1.3. Foreign Keys tab

Foreign Key management is performed via the Foreign Keys tab.

  • To add a foreign key, press the + button and set properties in the Foreign Keys Settings panel. You can set the foreign key name, referenced table name, foreign key columns and actions on update and delete.

  • To remove a foreign key, select the foreign key and press the - button.

  • To change foreign key settings, select the foreign key and use the Foreign Keys Settings panel to edit the properties.

  • When a foreign key is changed, the MySQL Visual Studio Plugin generates two queries: the first query drops the changed keys and the second one recreates the new values. The reason for such a behavior is to avoid the Bug#8377 and Bug#8919.

Note

If changed values are for some reason inconsistent and cause the second query to fail, all affected foreign keys will be dropped. If this is the case, the MySQL Visual Studio Plugin will mark them as new in the Table Editor, and you will have to recreate them later. But if you close the Table Editor without saving, these foreign keys will be lost.

27.3.3.1.4. Column Details tab

The Column Details tab can be used to set column options. Besides the main column properties that are presented in the Column Editor, in the Column Details tab you can set two additional properties options: the character set and the collation sequence.

27.3.3.1.5. Table Properties window

There is no separate tab for table options and advanced options. All table options can be browsed and changed using the Properties window of Visual Studio 2005.

The following table properties can be set:

  • Auto Increment

  • Average Row Length

  • Character Set

  • Checksum for Rows

  • Collation

  • Comment

  • Connection

  • Data Directory

  • Delay Key Updates

  • Engine

  • Index Directory

  • Insert Method

  • Maximum Rows

  • Minimum Rows

  • Name

  • Pack Keys

  • Password

  • Row Format

  • Union

Some of these properties can have arbitrary text values, others accept values from a predefined set.

The properties Schema and Server are read only.

27.3.3.2. Editing Table Data

The Table Data Editor, allows a user to browse, create and edit data of tables. The Table Data Editor is implemented as a simple data grid with auto generated columns.

To access the Table Data Editor, right click on a node representing the table or view in Server Explorer. From the nodes context menu, choose the Browse or Edit Data command. For tables and updatable views, this command opens the Table Data Editor in edit mode. For non-updatable views, this command opens the Table Data Editor in read-only mode.

When in the edit mode, you can modify table data by modifying the displayed table contents directly. To add a row, set desired values in the last row of the grid. To modify values, set new values in appropriate cells. To delete a row, select it by clicking on the selector column at the left of the grid, then press the Delete button.

To save changes you have made in the Table Data Editor, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Ctrl+S. A confirmation dialog will confirm whether you want the changes saved to the database.

27.3.3.3. Editing Views

To create a new view, right click the Views node under the connection node in Server Explorer. From the nodes context menu, choose the Create View command. This command opens the SQL Editor.

To modify an existing view, double click on a node of the view you wish to modify, or right click on this node and choose the Alter View command from a context menu. Either of the commands opens the SQL Editor.

To create or alter the view definition using SQL Editor, type the appropriate SQL statement in the SQL Editor.

Note

You should enter only the defining statement itself, without the CREATE VIEW AS preface.

All other view properties can be set in the Properties window. These properties are:

  • Algorithm

  • Check Option

  • Definer

  • Name

  • Security Type

Some of these properties can have arbitrary text values, others accept values from a predefined set.

The properties Is Updatable, Schema and Server are readonly.

To save changes you have made, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Ctrl+S. A confirmation dialog will confirm whether you want the changes saved to the database.

27.3.3.4. Editing Stored Procedures and Functions

To create a new stored procedure, right click the Stored Procedures node under the connection node in Server Explorer. From the nodes context menu, choose the Create Routine command. This command opens the SQL Editor.

To create a new stored function, right click the Functions node under the connection node in Server Explorer. From the node's context menu, choose the Create Routine command.

To modify an existing stored routine (procedure or function), double click on a node of the routine you wish to modify, or right click on this node and choose the Alter Routine command from a context menu. Either of the commands opens the SQL Editor.

To create or alter the routine definition using SQL Editor, type this definition in the SQL Editor using standard SQL.

All other routine properties can be set in the Properties window. These properties are:

  • Comment

  • Data Access

  • Definer

  • Is Deterministic

  • Security Type

Some of these properties can have arbitrary text values, others accept values only from a predefined set.

Also you can set all the options directly in the SQL Editor, using the standard CREATE PROCEDURE or CREATE FUNCTION statement. However, it is recommended to use the Properties window instead.

Note

You should never add the CREATE preface to the routine definition.

The properties Name, Schema and Server in the Properties window are read-only. Set or change the procedure name in the SQL editor.

To save changes you have made, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Ctrl+S. A confirmation dialog will confirm whether you want the changes saved to the database..

27.3.3.5. Editing Triggers

To create a new trigger, right click on a node of a table for which you wish to add a trigger. From the node's context menu, choose the Create Trigger command. This command opens the SQL Editor.

To modify an existing trigger, double click on a node of the trigger you wish to modify, or right click on this node and choose the Alter Trigger command from a context menu. Either of the commands opens the SQL Editor.

To create or alter the trigger definition using SQL Editor, type the trigger statement in the SQL Editor using standard SQL.

Note

You should enter only the trigger statement, that is the part of the CREATE TRIGGER query that is placed after the FOR EACH ROW clause.

All other trigger properties are set in the Properties window. These properties are:

  • Definer

  • Event Manipulation

  • Name

  • Timing

Some of these properties can have arbitrary text values, others accept values only from a predefined set.

The properties Event Table, Schema and Server in the Properties window are read-only.

To save changes you have made, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Ctrl+S. A confirmation dialog will confirm whether you want the changes saved to the database.

27.3.3.6. Editing User Defined Functions (UDF)

To create a new User Defined Function (UDF), right click the UDFs node under the connection node in Server Explorer. From the node's context menu, choose the Create UDF command. This command opens the UDF Editor.

To modify an existing UDF, double click on a node of the UDF you wish to modify, or right click on this node and choose the Alter UDF command from a context menu. Either of the commands opens the UDF Editor.

The UDF editor allows you to set the following properties through the properties panel:

  • Name

  • So-name (DLL name)

  • Return type

  • Is Aggregate

The property Server in the Properties window is read-only.

To save changes you have made, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Ctrl+S. A confirmation dialog will confirm whether you want the changes saved to the database.

27.3.3.7. Dropping database objects

Tables, views, stored routines, triggers, an UDFs can be dropped with the appropriate Drop command from its context menu: Drop Table, Drop View, Drop Routine, Drop Trigger, Drop UDF.

You will be asked to confirm the execution of the corresponding drop query in a confirmation dialog.

Dropping of multiple objects is not supported.

27.3.3.8. Cloning database objects

Tables, views, stored procedures and functions can be cloned with the appropriate Clone command from its context menu: Clone Table, Clone View, Clone Routine. The clone commands open the corresponding editor for a new object: the Table Editor for cloning a table and the SQL Editor for cloning a view or a routine.

To save the cloned object, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Ctrl+S. A confirmation dialog will confirm whether you want the changes saved to the database.

27.3.4. Visual Studio Plugin Support

If you have a comment, or if you discover a bug, please, use our MySQL bug tracking system (http://bugs.mysql.com) to report problem or add your suggestion.

27.3.4.1. Visual Studio Plugin FAQ

Questions

  • 28.3.4.1.1: When creating a connection, typing the connection details causes the connection window to immediately close.

Questions and Answers

28.3.4.1.1: When creating a connection, typing the connection details causes the connection window to immediately close.

There are known issues with versions of Connector/NET earlier than 5.0.2. Connector/NET 1.0.x is known not to work. If you have any of these versions installed, or have previously upgraded from an earlier version, uninstall Connector/NET completely and then install Connector/NET 5.0.2.

27.4. MySQL Connector/J

MySQL provides connectivity for client applications developed in the Java programming language via a JDBC driver, which is called MySQL Connector/J.

MySQL Connector/J is a JDBC Type 4 driver. Different versions are available that are compatible with the JDBC 3.0 and JDBC 4.0 specifications. The Type 4 designation means that the driver is pure-Java implementation of the MySQL protocol and does not rely on the MySQL client libraries.

Although JDBC is useful by itself, we would hope that if you are not familiar with JDBC that after reading the first few sections of this manual, that you would avoid using naked JDBC for all but the most trivial problems and consider using one of the popular persistence frameworks such as Hibernate, Spring's JDBC templates or Ibatis SQL Maps to do the majority of repetitive work and heavier lifting that is sometimes required with JDBC.

This section is not designed to be a complete JDBC tutorial. If you need more information about using JDBC you might be interested in the following online tutorials that are more in-depth than the information presented here:

Key topics:

MySQL Enterprise MySQL Enterprise subscribers will find more information about using JDBC with MySQL in the Knowledge Base articles about JDBC. Access to the MySQL Knowledge Base collection of articles is one of the advantages of subscribing to MySQL Enterprise. For more information see http://www.mysql.com/products/enterprise/advisors.html.

27.4.1. Connector/J Versions

There are currently four versions of MySQL Connector/J available:

  • Connector/J 5.1 is the Type 4 pure Java JDBC driver, which conforms to the JDBC 3.0 and JDBC 4.0 specifications. It provides compatibility with all the functionality of MySQL, including 4.1, 5.0, 5.1 and the 6.0 alpha release featuring the new Falcon storage engine. Connector/J 5.1 provides ease of development features, including auto-registration with the Driver Manager, standardized validity checks, categorized SQLExceptions, support for the JDBC-4.0 XML processing, per connection client information, NCHAR, NVARCHAR and NCLOB types. This release also includes all bug fixes up to and including Connector/J 5.0.6.

  • Connector/J 5.0 provides support for all the functionality offered by Connector/J 3.1 and includes distributed transaction (XA) support.

  • Connector/J 3.1 was designed for connectivity to MySQL 4.1 and MySQL 5.0 servers and provides support for all the functionality in MySQL 5.0 except distributed transaction (XA) support.

  • Connector/J 3.0 provides core functionality and was designed with connectivity to MySQL 3.x or MySQL 4.1 servers, although it will provide basic compatibility with later versions of MySQL. Connector/J 3.0 does not support server-side prepared statements, and does not support any of the features in versions of MySQL later than 4.1.

The following table summarizes the Connector/J versions available:

Connector/J versionDriver TypeJDBC versionMySQL Server versionStatus
5.143.0, 4.04.1, 5.0, 5.1, 6.0Recommended version
5.043.04.1, 5.0Released version
3.143.04.1, 5.0Obsolete
3.043.03.x, 4.1Obsolete

The current recommended version for Connector/J is 5.1. This guide covers all four connector versions, with specific notes given where a setting applies to a specific option.

27.4.1.1. Java Versions Supported

The following table summarizes Connector/J Java dependencies:

Connector/J versionJava RTE requiredJDK required (to build source code)
5.11.3.x, 1.4.x, 1.5.x, 1.6.x1.6.x and 1.5.x (or older)
5.01.3.x, 1.4.x, 1.5.x, 1.6.x1.4.2, 1.5.x, 1.6.x
3.11.2.x, 1.3.x, 1.4.x, 1.5.x, 1.6.x1.4.2, 1.5.x, 1.6.x
3.01.2.x, 1.3.x, 1.4.x, 1.5.x, 1.6.x1.4.2, 1.5.x, 1.6.x

MySQL Connector/J does not support JDK-1.1.x or JDK-1.0.x.

Because of the implementation of java.sql.Savepoint, Connector/J 3.1.0 and newer will not run on a Java runtime older than 1.4 unless the class verifier is turned off (by setting the -Xverify:none option to the Java runtime). This is because the class verifier will try to load the class definition for java.sql.Savepoint even though it is not accessed by the driver unless you actually use savepoint functionality.

Caching functionality provided by Connector/J 3.1.0 or newer is also not available on JVMs older than 1.4.x, as it relies on java.util.LinkedHashMap which was first available in JDK-1.4.0.

If you are building Connector/J from source code using the source distribution (see Section 27.4.2.4, “Installing from the Development Source Tree”) then you must use JDK 1.4.2 or newer to compile the Connector package. For Connector/J 5.1 you must have both JDK-1.6.x. and JDK-1.5.x installed in order to be able to build the source code.

27.4.2. Connector/J Installation

You can install the Connector/J package using either the binary or source distribution. The binary distribution provides the easiest method for installation; the source distribution enables you to customize your installation further. With either solution, you must manually add the Connector/J location to your Java CLASSPATH.

If you are upgrading from a previous version, read the upgrade information before continuing. See Section 27.4.2.3, “Upgrading from an Older Version”.

27.4.2.1. Installing Connector/J from a Binary Distribution

The easiest method of installation is to use the binary distribution of the Connector/J package. The binary distribution is available either as a Tar/Gzip or Zip file which you must extract to a suitable location and then optionally make the information about the package available by changing your CLASSPATH (see Section 27.4.2.2, “Installing the Driver and Configuring the CLASSPATH).

MySQL Connector/J is distributed as a .zip or .tar.gz archive containing the sources, the class files, and the JAR archive named mysql-connector-java-[version]-bin.jar, and starting with Connector/J 3.1.8 a debug build of the driver in a file named mysql-connector-java-[version]-bin-g.jar.

Starting with Connector/J 3.1.9, the .class files that constitute the JAR files are only included as part of the driver JAR file.

You should not use the debug build of the driver unless instructed to do so when reporting a problem or a bug to MySQL AB, as it is not designed to be run in production environments, and will have adverse performance impact when used. The debug binary also depends on the Aspect/J runtime library, which is located in the src/lib/aspectjrt.jar file that comes with the Connector/J distribution.

You will need to use the appropriate graphical or command-line utility to extract the distribution (for example, WinZip for the .zip archive, and tar for the .tar.gz archive). Because there are potentially long filenames in the distribution, we use the GNU tar archive format. You will need to use GNU tar (or an application that understands the GNU tar archive format) to unpack the .tar.gz variant of the distribution.

27.4.2.2. Installing the Driver and Configuring the CLASSPATH

Once you have extracted the distribution archive, you can install the driver by placing mysql-connector-java-[version]-bin.jar in your classpath, either by adding the full path to it to your CLASSPATH environment variable, or by directly specifying it with the command line switch -cp when starting your JVM.

If you are going to use the driver with the JDBC DriverManager, you would use com.mysql.jdbc.Driver as the class that implements java.sql.Driver.

You can set the CLASSPATH environment variable under UNIX, Linux or Mac OS X either locally for a user within their .profile, .login or other login file. You can also set it globally by editing the global /etc/profile file.

For example, under a C shell (csh, tcsh) you would add the Connector/J driver to your CLASSPATH using the following:

shell> setenv CLASSPATH /path/mysql-connector-java-[ver]-bin.jar:$CLASSPATH

Or with a Bourne-compatible shell (sh, ksh, bash):

shell> export set CLASSPATH=/path/mysql-connector-java-[ver]-bin.jar:$CLASSPATH

Within Windows 2000, Windows XP, Windows Server 2003 and Windows Vista, you must set the environment variable through the System Control Panel.

If you want to use MySQL Connector/J with an application server such as GlassFish, Tomcat or JBoss, you will have to read your vendor's documentation for more information on how to configure third-party class libraries, as most application servers ignore the CLASSPATH environment variable. For configuration examples for some J2EE application servers, see Section 27.4.5.2, “Using Connector/J with J2EE and Other Java Frameworks”. However, the authoritative source for JDBC connection pool configuration information for your particular application server is the documentation for that application server.

If you are developing servlets or JSPs, and your application server is J2EE-compliant, you can put the driver's .jar file in the WEB-INF/lib subdirectory of your webapp, as this is a standard location for third party class libraries in J2EE web applications.

You can also use the MysqlDataSource or MysqlConnectionPoolDataSource classes in the com.mysql.jdbc.jdbc2.optional package, if your J2EE application server supports or requires them. Starting with Connector/J 5.0.0, the javax.sql.XADataSource interface is implemented via the com.mysql.jdbc.jdbc2.optional.MysqlXADataSource class, which supports XA distributed transactions when used in combination with MySQL server version 5.0.

The various MysqlDataSource classes support the following parameters (through standard set mutators):

  • user

  • password

  • serverName (see the previous section about fail-over hosts)

  • databaseName

  • port

27.4.2.3. Upgrading from an Older Version

MySQL AB tries to keep the upgrade process as easy as possible, however as is the case with any software, sometimes changes need to be made in new versions to support new features, improve existing functionality, or comply with new standards.

This section has information about what users who are upgrading from one version of Connector/J to another (or to a new version of the MySQL server, with respect to JDBC functionality) should be aware of.

27.4.2.3.1. Upgrading from MySQL Connector/J 3.0 to 3.1

Connector/J 3.1 is designed to be backward-compatible with Connector/J 3.0 as much as possible. Major changes are isolated to new functionality exposed in MySQL-4.1 and newer, which includes Unicode character sets, server-side prepared statements, SQLState codes returned in error messages by the server and various performance enhancements that can be enabled or disabled via configuration properties.

  • Unicode Character Sets — See the next section, as well as Section 9.1, “Character Set Support”, for information on this new feature of MySQL. If you have something misconfigured, it will usually show up as an error with a message similar to Illegal mix of collations.

  • Server-side Prepared Statements — Connector/J 3.1 will automatically detect and use server-side prepared statements when they are available (MySQL server version 4.1.0 and newer).

    Starting with version 3.1.7, the driver scans SQL you are preparing via all variants of Connection.prepareStatement() to determine if it is a supported type of statement to prepare on the server side, and if it is not supported by the server, it instead prepares it as a client-side emulated prepared statement. You can disable this feature by passing emulateUnsupportedPstmts=false in your JDBC URL.

    If your application encounters issues with server-side prepared statements, you can revert to the older client-side emulated prepared statement code that is still presently used for MySQL servers older than 4.1.0 with the connection property useServerPrepStmts=false

  • Datetimes with all-zero components (0000-00-00 ...) — These values can not be represented reliably in Java. Connector/J 3.0.x always converted them to NULL when being read from a ResultSet.

    Connector/J 3.1 throws an exception by default when these values are encountered as this is the most correct behavior according to the JDBC and SQL standards. This behavior can be modified using the zeroDateTimeBehavior configuration property. The allowable values are:

    • exception (the default), which throws an SQLException with an SQLState of S1009.

    • convertToNull, which returns NULL instead of the date.

    • round, which rounds the date to the nearest closest value which is 0001-01-01.

    Starting with Connector/J 3.1.7, ResultSet.getString() can be decoupled from this behavior via noDatetimeStringSync=true (the default value is false) so that you can retrieve the unaltered all-zero value as a String. It should be noted that this also precludes using any time zone conversions, therefore the driver will not allow you to enable noDatetimeStringSync and useTimezone at the same time.

  • New SQLState Codes — Connector/J 3.1 uses SQL:1999 SQLState codes returned by the MySQL server (if supported), which are different from the legacy X/Open state codes that Connector/J 3.0 uses. If connected to a MySQL server older than MySQL-4.1.0 (the oldest version to return SQLStates as part of the error code), the driver will use a built-in mapping. You can revert to the old mapping by using the configuration property useSqlStateCodes=false.

  • ResultSet.getString() — Calling ResultSet.getString() on a BLOB column will now return the address of the byte[] array that represents it, instead of a String representation of the BLOB. BLOBs have no character set, so they can't be converted to java.lang.Strings without data loss or corruption.

    To store strings in MySQL with LOB behavior, use one of the TEXT types, which the driver will treat as a java.sql.Clob.

  • Debug builds — Starting with Connector/J 3.1.8 a debug build of the driver in a file named mysql-connector-java-[version]-bin-g.jar is shipped alongside the normal binary jar file that is named mysql-connector-java-[version]-bin.jar.

    Starting with Connector/J 3.1.9, we don't ship the .class files unbundled, they are only available in the JAR archives that ship with the driver.

    You should not use the debug build of the driver unless instructed to do so when reporting a problem or bug to MySQL AB, as it is not designed to be run in production environments, and will have adverse performance impact when used. The debug binary also depends on the Aspect/J runtime library, which is located in the src/lib/aspectjrt.jar file that comes with the Connector/J distribution.

27.4.2.3.2. Upgrading to MySQL Connector/J 5.1.x
  • In Connector/J 5.0.x and earlier, the alias for a table in a SELECT statement is returned when accessing the result set metadata using ResultSetMetaData.getColumnName(). This behavior however is not JDBC compliant, and in Connector/J 5.1 this behavior was changed so that the original table name, rather than the alias, is returned.

    The JDBC-compliant behavior is designed to let API users reconstruct the DML statement based on the metadata within ResultSet and ResultSetMetaData.

    You can get the alias for a column in a result set by calling ResultSetMetaData.getColumnLabel(). If you want to use the old non-compliant behavior with ResultSetMetaData.getColumnName(), use the useOldAliasMetadataBehavior option and set the value to true.

    In Connector/J 5.0.x the default value of useOldAliasMetadataBehavior was true, but in Connector/J 5.1 this was changed to a default value of false.

27.4.2.3.3. JDBC-Specific Issues When Upgrading to MySQL Server 4.1 or Newer
  • Using the UTF-8 Character Encoding - Prior to MySQL server version 4.1, the UTF-8 character encoding was not supported by the server, however the JDBC driver could use it, allowing storage of multiple character sets in latin1 tables on the server.

    Starting with MySQL-4.1, this functionality is deprecated. If you have applications that rely on this functionality, and can not upgrade them to use the official Unicode character support in MySQL server version 4.1 or newer, you should add the following property to your connection URL:

    useOldUTF8Behavior=true

  • Server-side Prepared Statements - Connector/J 3.1 will automatically detect and use server-side prepared statements when they are available (MySQL server version 4.1.0 and newer). If your application encounters issues with server-side prepared statements, you can revert to the older client-side emulated prepared statement code that is still presently used for MySQL servers older than 4.1.0 with the following connection property:

    useServerPrepStmts=false

27.4.2.4. Installing from the Development Source Tree

Caution

You should read this section only if you are interested in helping us test our new code. If you just want to get MySQL Connector/J up and running on your system, you should use a standard binary release distribution.

To install MySQL Connector/J from the development source tree, make sure that you have the following prerequisites:

  • Subversion, to check out the sources from our repository (available from http://subversion.tigris.org/).

  • Apache Ant version 1.7 or newer (available from http://ant.apache.org/).

  • JDK 1.4.2 or later. Although MySQL Connector/J can be be used with older JDKs, to compile it from source you must have at least JDK 1.4.2. If you are building Connector/J 5.1 you will need JDK 1.6.x and an older JDK such as JDK 1.5.x. You will then need to point your JAVA_HOME environment variable at the older installation.

The Subversion source code repository for MySQL Connector/J is located at http://svn.mysql.com/svnpublic/connector-j. In general, you should not check out the entire repository because it contains every branch and tag for MySQL Connector/J and is quite large.

To check out and compile a specific branch of MySQL Connector/J, follow these steps:

  1. Check out the latest code from the branch that you want with the following command (replacing [major] and [minor] with appropriate version numbers):

    shell> svn co »
    http://svn.mysql.com/svnpublic/connector-j/branches/branch_[major]_[minor] connector-j

    This creates a connector-j subdirectory in the current directory that contains the latest sources for the requested branch.

  2. If you are building Connector/J 5.1 make sure that you have both JDK 1.6.x installed and an older JDK such as JDK 1.5.x. This is because Connector/J supports both JDBC 3.0 (which was prior to JDK 1.6.x) and JDBC 4.0. Set your JAVA_HOME environment variable to the path of the older JDK installation.

  3. Change location to the connector-j directory to make it your current working directory:

    shell> cd connector-j
  4. If you are building Connector/J 5.1 you need to edit the build.xml to reflect the location of your JDK 1.6.x installation. The lines that you need to change are:

                <property name="com.mysql.jdbc.java6.javac" value="C:\jvms\jdk1.6.0\bin\javac.exe" />
                <property name="com.mysql.jdbc.java6.rtjar" value="C:\jvms\jdk1.6.0\jre\lib\rt.jar" />
              

    Alternatively, you can set the value of these property names through the Ant -D option.

  5. Issue the following command to compile the driver and create a .jar file suitable for installation:

    shell> ant dist

    This creates a build directory in the current directory, where all build output will go. A directory is created in the build directory that includes the version number of the sources you are building from. This directory contains the sources, compiled .class files, and a .jar file suitable for deployment. For other possible targets, including ones that will create a fully packaged distribution, issue the following command:

    shell> ant -projecthelp
  6. A newly created .jar file containing the JDBC driver will be placed in the directory build/mysql-connector-java-[version].

    Install the newly created JDBC driver as you would a binary .jar file that you download from MySQL by following the instructions in Section 27.4.2.2, “Installing the Driver and Configuring the CLASSPATH.

A package containing both the binary and source code for Connector/J 5.1 can also be found at the following location: Connector/J 5.1 Download

27.4.4. Connector/J (JDBC) Reference

This section of the manual contains reference material for MySQL Connector/J, some of which is automatically generated during the Connector/J build process.

27.4.4.1. Driver/Datasource Class Names, URL Syntax and Configuration Properties for Connector/J

The name of the class that implements java.sql.Driver in MySQL Connector/J is com.mysql.jdbc.Driver. The org.gjt.mm.mysql.Driver class name is also usable to remain backward-compatible with MM.MySQL. You should use this class name when registering the driver, or when otherwise configuring software to use MySQL Connector/J.

The JDBC URL format for MySQL Connector/J is as follows, with items in square brackets ([, ]) being optional:

jdbc:mysql://[host][,failoverhost...][:port]/[database] »
[?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...

If the hostname is not specified, it defaults to 127.0.0.1. If the port is not specified, it defaults to 3306, the default port number for MySQL servers.

jdbc:mysql://[host:port],[host:port].../[database] »
[?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...

If the database is not specified, the connection will be made with no default database. In this case, you will need to either call the setCatalog() method on the Connection instance or fully-specify table names using the database name (i.e. SELECT dbname.tablename.colname FROM dbname.tablename...) in your SQL. Not specifying the database to use upon connection is generally only useful when building tools that work with multiple databases, such as GUI database managers.

MySQL Connector/J has fail-over support. This allows the driver to fail-over to any number of slave hosts and still perform read-only queries. Fail-over only happens when the connection is in an autoCommit(true) state, because fail-over can not happen reliably when a transaction is in progress. Most application servers and connection pools set autoCommit to true at the end of every transaction/connection use.

The fail-over functionality has the following behavior:

  • If the URL property autoReconnect is false: Failover only happens at connection initialization, and failback occurs when the driver determines that the first host has become available again.

  • If the URL property autoReconnect is true: Failover happens when the driver determines that the connection has failed (before every query), and falls back to the first host when it determines that the host has become available again (after queriesBeforeRetryMaster queries have been issued).

In either case, whenever you are connected to a "failed-over" server, the connection will be set to read-only state, so queries that would modify data will have exceptions thrown (the query will never be processed by the MySQL server).

Configuration properties define how Connector/J will make a connection to a MySQL server. Unless otherwise noted, properties can be set for a DataSource object or for a Connection object.

Configuration Properties can be set in one of the following ways:

  • Using the set*() methods on MySQL implementations of java.sql.DataSource (which is the preferred method when using implementations of java.sql.DataSource):

    • com.mysql.jdbc.jdbc2.optional.MysqlDataSource

    • com.mysql.jdbc.jdbc2.optional.MysqlConnectionPoolDataSource

  • As a key/value pair in the java.util.Properties instance passed to DriverManager.getConnection() or Driver.connect()

  • As a JDBC URL parameter in the URL given to java.sql.DriverManager.getConnection(), java.sql.Driver.connect() or the MySQL implementations of the javax.sql.DataSource setURL() method.

    Note

    If the mechanism you use to configure a JDBC URL is XML-based, you will need to use the XML character literal &amp; to separate configuration parameters, as the ampersand is a reserved character for XML.

The properties are listed in the following tables.

Connection/Authentication. 

Property Name Definition Default Value Since Version
userThe user to connect as all versions
passwordThe password to use when connecting all versions
socketFactoryThe name of the class that the driver should use for creating socket connections to the server. This class must implement the interface 'com.mysql.jdbc.SocketFactory' and have public no-args constructor.com.mysql.jdbc.StandardSocketFactory3.0.3
connectTimeoutTimeout for socket connect (in milliseconds), with 0 being no timeout. Only works on JDK-1.4 or newer. Defaults to '0'.03.0.1
socketTimeoutTimeout on network socket operations (0, the default means no timeout).03.0.1
connectionLifecycleInterceptorsA comma-delimited list of classes that implement "com.mysql.jdbc.ConnectionLifecycleInterceptor" that should notified of connection lifecycle events (creation, destruction, commit, rollback, setCatalog and setAutoCommit) and potentially alter the execution of these commands. ConnectionLifecycleInterceptors are "stackable", more than one interceptor may be specified via the configuration property as a comma-delimited list, with the interceptors executed in order from left to right. 5.1.4
useConfigsLoad the comma-delimited list of configuration properties before parsing the URL or applying user-specified properties. These configurations are explained in the 'Configurations' of the documentation. 3.1.5
interactiveClientSet the CLIENT_INTERACTIVE flag, which tells MySQL to timeout connections based on INTERACTIVE_TIMEOUT instead of WAIT_TIMEOUTfalse3.1.0
localSocketAddressHostname or IP address given to explicitly configure the interface that the driver will bind the client side of the TCP/IP connection to when connecting. 5.0.5
mysqlIOFactoryThe name of the class which implements "com.mysql.jdbc.MysqlIO" for communicating with mysqld. (default is "com.mysql.jdbc.MysqlIOprotocol")com.mysql.jdbc.MysqlIOprotocol6.0.0
propertiesTransformAn implementation of com.mysql.jdbc.ConnectionPropertiesTransform that the driver will use to modify URL properties passed to the driver before attempting a connection 3.1.4
useCompressionUse zlib compression when communicating with the server (true/false)? Defaults to 'false'.false3.0.17

Networking. 

Property Name Definition Default Value Since Version
tcpKeepAliveIf connecting using TCP/IP, should the driver set SO_KEEPALIVE?true5.0.7
tcpNoDelayIf connecting using TCP/IP, should the driver set SO_TCP_NODELAY (disabling the Nagle Algorithm)?true5.0.7
tcpRcvBufIf connecting using TCP/IP, should the driver set SO_RCV_BUF to the given value? The default value of '0', means use the platform default value for this property)05.0.7
tcpSndBufIf connecting using TCP/IP, shuold the driver set SO_SND_BUF to the given value? The default value of '0', means use the platform default value for this property)05.0.7
tcpTrafficClassIf connecting using TCP/IP, should the driver set traffic class or type-of-service fields ?See the documentation for java.net.Socket.setTrafficClass() for more information.05.0.7

High Availability and Clustering. 

Property Name Definition Default Value Since Version
autoReconnectShould the driver try to re-establish stale and/or dead connections? If enabled the driver will throw an exception for a queries issued on a stale or dead connection, which belong to the current transaction, but will attempt reconnect before the next query issued on the connection in a new transaction. The use of this feature is not recommended, because it has side effects related to session state and data consistency when applications don't handle SQLExceptions properly, and is only designed to be used when you are unable to configure your application to handle SQLExceptions resulting from dead and stale connections properly. Alternatively, investigate setting the MySQL server variable "wait_timeout" to some high value rather than the default of 8 hours.false1.1
autoReconnectForPoolsUse a reconnection strategy appropriate for connection pools (defaults to 'false')false3.1.3
failOverReadOnlyWhen failing over in autoReconnect mode, should the connection be set to 'read-only'?true3.0.12
maxReconnectsMaximum number of reconnects to attempt if autoReconnect is true, default is '3'.31.1
reconnectAtTxEndIf autoReconnect is set to true, should the driver attempt reconnections at the end of every transaction?false3.0.10
initialTimeoutIf autoReconnect is enabled, the initial time to wait between re-connect attempts (in seconds, defaults to '2').21.1
roundRobinLoadBalanceWhen autoReconnect is enabled, and failoverReadonly is false, should we pick hosts to connect to on a round-robin basis?false3.1.2
queriesBeforeRetryMasterNumber of queries to issue before falling back to master when failed over (when using multi-host failover). Whichever condition is met first, 'queriesBeforeRetryMaster' or 'secondsBeforeRetryMaster' will cause an attempt to be made to reconnect to the master. Defaults to 50.503.0.2
secondsBeforeRetryMasterHow long should the driver wait, when failed over, before attempting303.0.2
selfDestructOnPingMaxOperations=If set to a non-zero value, the driver will report close the connection and report failure when Connection.ping() or Connection.isValid(int) is called if the connnection's count of commands sent to the server exceeds this value.05.1.6
selfDestructOnPingSecondsLifetimeIf set to a non-zero value, the driver will report close the connection and report failure when Connection.ping() or Connection.isValid(int) is called if the connnection's lifetime exceeds this value.05.1.6
resourceIdA globally unique name that identifies the resource that this datasource or connection is connected to, used for XAResource.isSameRM() when the driver can't determine this value based on hostnames used in the URL 5.0.1

Security. 

Property Name Definition Default Value Since Version
allowMultiQueriesAllow the use of ';' to delimit multiple queries during one statement (true/false), defaults to 'false'false3.1.1
useSSLUse SSL when communicating with the server (true/false), defaults to 'false'false3.0.2
requireSSLRequire SSL connection if useSSL=true? (defaults to 'false').false3.1.0
verifyServerCertificateIf "useSSL" is set to "true", should the driver verify the server's certificate? When using this feature, the keystore parameters should be specified by the "clientCertificateKeyStore*" properties, rather than system properties.true5.1.6
clientCertificateKeyStoreUrlURL to the client certificate KeyStore (if not specified, use defaults) 5.1.0
clientCertificateKeyStoreTypeKeyStore type for client certificates (NULL or empty means use default, standard keystore types supported by the JVM are "JKS" and "PKCS12", your environment may have more available depending on what security products are installed and available to the JVM. 5.1.0
clientCertificateKeyStorePasswordPassword for the client certificates KeyStore 5.1.0
trustCertificateKeyStoreUrlURL to the trusted root certificate KeyStore (if not specified, use defaults) 5.1.0
trustCertificateKeyStoreTypeKeyStore type for trusted root certificates (NULL or empty means use default, standard keystore types supported by the JVM are "JKS" and "PKCS12", your environment may have more available depending on what security products are installed and available to the JVM. 5.1.0
trustCertificateKeyStorePasswordPassword for the trusted root certificates KeyStore 5.1.0
allowLoadLocalInfileShould the driver allow use of 'LOAD DATA LOCAL INFILE...' (defaults to 'true').true3.0.3
allowUrlInLocalInfileShould the driver allow URLs in 'LOAD DATA LOCAL INFILE' statements?false3.1.4
paranoidTake measures to prevent exposure sensitive information in error messages and clear data structures holding sensitive data when possible? (defaults to 'false')false3.0.1

Performance Extensions. 

Property Name Definition Default Value Since Version
callableStmtCacheSizeIf 'cacheCallableStmts' is enabled, how many callable statements should be cached?1003.1.2
metadataCacheSizeThe number of queries to cache ResultSetMetadata for if cacheResultSetMetaData is set to 'true' (default 50)503.1.1
prepStmtCacheSizeIf prepared statement caching is enabled, how many prepared statements should be cached?253.0.10
prepStmtCacheSqlLimitIf prepared statement caching is enabled, what's the largest SQL the driver will cache the parsing for?2563.0.10
alwaysSendSetIsolationShould the driver always communicate with the database when Connection.setTransactionIsolation() is called? If set to false, the driver will only communicate with the database when the requested transaction isolation is different than the whichever is newer, the last value that was set via Connection.setTransactionIsolation(), or the value that was read from the server when the connection was established.true3.1.7
maintainTimeStatsShould the driver maintain various internal timers to enable idle time calculations as well as more verbose error messages when the connection to the server fails? Setting this property to false removes at least two calls to System.getCurrentTimeMillis() per query.true3.1.9
useCursorFetchIf connected to MySQL > 5.0.2, and setFetchSize() > 0 on a statement, should that statement use cursor-based fetching to retrieve rows?false5.0.0
blobSendChunkSizeChunk to use when sending BLOB/CLOBs via ServerPreparedStatements10485763.1.9
cacheCallableStmtsShould the driver cache the parsing stage of CallableStatementsfalse3.1.2
cachePrepStmtsShould the driver cache the parsing stage of PreparedStatements of client-side prepared statements, the "check" for suitability of server-side prepared and server-side prepared statements themselves?false3.0.10
cacheResultSetMetadataShould the driver cache ResultSetMetaData for Statements and PreparedStatements? (Req. JDK-1.4+, true/false, default 'false')false3.1.1
cacheServerConfigurationShould the driver cache the results of 'SHOW VARIABLES' and 'SHOW COLLATION' on a per-URL basis?false3.1.5
defaultFetchSizeThe driver will call setFetchSize(n) with this value on all newly-created Statements03.1.9
dontTrackOpenResourcesThe JDBC specification requires the driver to automatically track and close resources, however if your application doesn't do a good job of explicitly calling close() on statements or result sets, this can cause memory leakage. Setting this property to true relaxes this constraint, and can be more memory efficient for some applications.false3.1.7
dynamicCalendarsShould the driver retrieve the default calendar when required, or cache it per connection/session?false3.1.5
elideSetAutoCommitsIf using MySQL-4.1 or newer, should the driver only issue 'set autocommit=n' queries when the server's state doesn't match the requested state by Connection.setAutoCommit(boolean)?false3.1.3
enableQueryTimeoutsWhen enabled, query timeouts set via Statement.setQueryTimeout() use a shared java.util.Timer instance for scheduling. Even if the timeout doesn't expire before the query is processed, there will be memory used by the TimerTask for the given timeout which won't be reclaimed until the time the timeout would have expired if it hadn't been cancelled by the driver. High-load environments might want to consider disabling this functionality.true5.0.6
holdResultsOpenOverStatementCloseShould the driver close result sets on Statement.close() as required by the JDBC specification?false3.1.7
largeRowSizeThresholdWhat size result set row should the JDBC driver consider "large", and thus use a more memory-efficient way of representing the row internally?20485.1.1
loadBalanceStrategyIf using a load-balanced connection to connect to SQL nodes in a MySQL Cluster/NDB configuration (by using the URL prefix "jdbc:mysql:loadbalance://"), which load balancing algorithm should the driver use: (1) "random" - the driver will pick a random host for each request. This tends to work better than round-robin, as the randomness will somewhat account for spreading loads where requests vary in response time, while round-robin can sometimes lead to overloaded nodes if there are variations in response times across the workload. (2) "bestResponseTime" - the driver will route the request to the host that had the best response time for the previous transaction.random5.0.6
locatorFetchBufferSizeIf 'emulateLocators' is configured to 'true', what size buffer should be used when fetching BLOB data for getBinaryInputStream?10485763.2.1
rewriteBatchedStatementsShould the driver use multiqueries (irregardless of the setting of "allowMultiQueries") as well as rewriting of prepared statements for INSERT into multi-value inserts when executeBatch() is called? Notice that this has the potential for SQL injection if using plain java.sql.Statements and your code doesn't sanitize input correctly. Notice that for prepared statements, server-side prepared statements can not currently take advantage of this rewrite option, and that if you don't specify stream lengths when using PreparedStatement.set*Stream(), the driver won't be able to determine the optimum number of parameters per batch and you might receive an error from the driver that the resultant packet is too large. Statement.getGeneratedKeys() for these rewritten statements only works when the entire batch includes INSERT statements.false3.1.13
useDirectRowUnpackUse newer result set row unpacking code that skips a copy from network buffers to a MySQL packet instance and instead reads directly into the result set row data buffers.true5.1.1
useDynamicCharsetInfoShould the driver use a per-connection cache of character set information queried from the server when necessary, or use a built-in static mapping that is more efficient, but isn't aware of custom character sets or character sets implemented after the release of the JDBC driver?true5.0.6
useFastDateParsingUse internal String->Date/Time/Timestamp conversion routines to avoid excessive object creation?true5.0.5
useFastIntParsingUse internal String->Integer conversion routines to avoid excessive object creation?true3.1.4
useJvmCharsetConvertersAlways use the character encoding routines built into the JVM, rather than using lookup tables for single-byte character sets?false5.0.1
useLocalSessionStateShould the driver refer to the internal values of autocommit and transaction isolation that are set by Connection.setAutoCommit() and Connection.setTransactionIsolation() and transaction state as maintained by the protocol, rather than querying the database or blindly sending commands to the database for commit() or rollback() method calls?false3.1.7
useReadAheadInputUse newer, optimized non-blocking, buffered input stream when reading from the server?true3.1.5

Debugging/Profiling. 

Property Name Definition Default Value Since Version
loggerThe name of a class that implements "com.mysql.jdbc.log.Log" that will be used to log messages to. (default is "com.mysql.jdbc.log.StandardLogger", which logs to STDERR)com.mysql.jdbc.log.StandardLogger3.1.1
gatherPerfMetricsShould the driver gather performance metrics, and report them via the configured logger every 'reportMetricsIntervalMillis' milliseconds?false3.1.2
profileSQLTrace queries and their execution/fetch times to the configured logger (true/false) defaults to 'false'false3.1.0
profileSqlDeprecated, use 'profileSQL' instead. Trace queries and their execution/fetch times on STDERR (true/false) defaults to 'false' 2.0.14
reportMetricsIntervalMillisIf 'gatherPerfMetrics' is enabled, how often should they be logged (in ms)?300003.1.2
maxQuerySizeToLogControls the maximum length/size of a query that will get logged when profiling or tracing20483.1.3
packetDebugBufferSizeThe maximum number of packets to retain when 'enablePacketDebug' is true203.1.3
slowQueryThresholdMillisIf 'logSlowQueries' is enabled, how long should a query (in ms) before it is logged as 'slow'?20003.1.2
slowQueryThresholdNanosIf 'useNanosForElapsedTime' is set to true, and this property is set to a non-zero value, the driver will use this threshold (in nanosecond units) to determine if a query was slow.05.0.7
useUsageAdvisorShould the driver issue 'usage' warnings advising proper and efficient usage of JDBC and MySQL Connector/J to the log (true/false, defaults to 'false')?false3.1.1
autoGenerateTestcaseScriptShould the driver dump the SQL it is executing, including server-side prepared statements to STDERR?false3.1.9
autoSlowLogInstead of using slowQueryThreshold* to determine if a query is slow enough to be logged, maintain statistics that allow the driver to determine queries that are outside the 99th percentile?true5.1.4
clientInfoProviderThe name of a class that implements the com.mysql.jdbc.JDBC4ClientInfoProvider interface in order to support JDBC-4.0's Connection.get/setClientInfo() methodscom.mysql.jdbc.JDBC4CommentClientInfoProvider5.1.0
dumpMetadataOnColumnNotFoundShould the driver dump the field-level metadata of a result set into the exception message when ResultSet.findColumn() fails?false3.1.13
dumpQueriesOnExceptionShould the driver dump the contents of the query sent to the server in the message for SQLExceptions?false3.1.3
enablePacketDebugWhen enabled, a ring-buffer of 'packetDebugBufferSize' packets will be kept, and dumped when exceptions are thrown in key areas in the driver's codefalse3.1.3
explainSlowQueriesIf 'logSlowQueries' is enabled, should the driver automatically issue an 'EXPLAIN' on the server and send the results to the configured log at a WARN level?false3.1.2
includeInnodbStatusInDeadlockExceptionsInclude the output of "SHOW ENGINE INNODB STATUS" in exception messages when deadlock exceptions are detected?false5.0.7
logSlowQueriesShould queries that take longer than 'slowQueryThresholdMillis' be logged?false3.1.2
logXaCommandsShould the driver log XA commands sent by MysqlXaConnection to the server, at the DEBUG level of logging?false5.0.5
profilerEventHandlerName of a class that implements the interface com.mysql.jdbc.profiler.ProfilerEventHandler that will be used to handle profiling/tracing events.com.mysql.jdbc.profiler.LoggingProfilerEventHandler5.1.6
resultSetSizeThresholdIf the usage advisor is enabled, how many rows should a result set contain before the driver warns that it is suspiciously large?1005.0.5
traceProtocolShould trace-level network protocol be logged?false3.1.2
useNanosForElapsedTimeFor profiling/debugging functionality that measures elapsed time, should the driver try to use nanoseconds resolution if available (JDK >= 1.5)?false5.0.7

Miscellaneous. 

Property Name Definition Default Value Since Version
useUnicodeShould the driver use Unicode character encodings when handling strings? Should only be used when the driver can't determine the character set mapping, or you are trying to 'force' the driver to use a character set that MySQL either doesn't natively support (such as UTF-8), true/false, defaults to 'true'true1.1g
characterEncodingIf 'useUnicode' is set to true, what character encoding should the driver use when dealing with strings? (defaults is to 'autodetect') 1.1g
characterSetResultsCharacter set to tell the server to return results as. 3.0.13
connectionCollationIf set, tells the server to use this collation via 'set collation_connection' 3.0.13
useBlobToStoreUTF8OutsideBMPTells the driver to treat [MEDIUM/LONG]BLOB columns as [LONG]VARCHAR columns holding text encoded in UTF-8 that has characters outside the BMP (4-byte encodings), which MySQL server can't handle natively.false5.1.3
utf8OutsideBmpExcludedColumnNamePatternWhen "useBlobToStoreUTF8OutsideBMP" is set to "true", column names matching the given regex will still be treated as BLOBs unless they match the regex specified for "utf8OutsideBmpIncludedColumnNamePattern". The regex must follow the patterns used for the java.util.regex package. 5.1.3
utf8OutsideBmpIncludedColumnNamePatternUsed to specify exclusion rules to "utf8OutsideBmpExcludedColumnNamePattern". The regex must follow the patterns used for the java.util.regex package. 5.1.3
sessionVariablesA comma-separated list of name/value pairs to be sent as SET SESSION ... to the server when the driver connects. 3.1.8
allowNanAndInfShould the driver allow NaN or +/- INF values in PreparedStatement.setDouble()?false3.1.5
autoClosePStmtStreamsShould the driver automatically call .close() on streams/readers passed as arguments via set*() methods?false3.1.12
autoDeserializeShould the driver automatically detect and de-serialize objects stored in BLOB fields?false3.1.5
blobsAreStringsShould the driver always treat BLOBs as Strings - specifically to work around dubious metadata returned by the server for GROUP BY clauses?false5.0.8
capitalizeTypeNamesCapitalize type names in DatabaseMetaData? (usually only useful when using WebObjects, true/false, defaults to 'false')true2.0.7
clobCharacterEncodingThe character encoding to use for sending and retrieving TEXT, MEDIUMTEXT and LONGTEXT values instead of the configured connection characterEncoding 5.0.0
clobberStreamingResultsThis will cause a 'streaming' ResultSet to be automatically closed, and any outstanding data still streaming from the server to be discarded if another query is executed before all the data has been read from the server.false3.0.9
continueBatchOnErrorShould the driver continue processing batch commands if one statement fails. The JDBC spec allows either way (defaults to 'true').true3.0.3
createDatabaseIfNotExistCreates the database given in the URL if it doesn't yet exist. Assumes the configured user has permissions to create databases.false3.1.9
emptyStringsConvertToZeroShould the driver allow conversions from empty string fields to numeric values of '0'?true3.1.8
emulateLocatorsShould the driver emulate java.sql.Blobs with locators? With this feature enabled, the driver will delay loading the actual Blob data until the one of the retrieval methods (getInputStream(), getBytes(), and so forth) on the blob data stream has been accessed. For this to work, you must use a column alias with the value of the column to the actual name of the Blob. The feature also has the following restrictions: The SELECT that created the result set must reference only one table, the table must have a primary key; the SELECT must alias the original blob column name, specified as a string, to an alternate name; the SELECT must cover all columns that make up the primary key.false3.1.0
emulateUnsupportedPstmtsShould the driver detect prepared statements that are not supported by the server, and replace them with client-side emulated versions?true3.1.7
functionsNeverReturnBlobsShould the driver always treat data from functions returning BLOBs as Strings - specifically to work around dubious metadata returned by the server for GROUP BY clauses?false5.0.8
generateSimpleParameterMetadataShould the driver generate simplified parameter metadata for PreparedStatements when no metadata is available either because the server couldn't support preparing the statement, or server-side prepared statements are disabled?false5.0.5
ignoreNonTxTablesIgnore non-transactional table warning for rollback? (defaults to 'false').false3.0.9
jdbcCompliantTruncationShould the driver throw java.sql.DataTruncation exceptions when data is truncated as is required by the JDBC specification when connected to a server that supports warnings (MySQL 4.1.0 and newer)? This property has no effect if the server sql-mode includes STRICT_TRANS_TABLES.true3.1.2
maxRowsThe maximum number of rows to return (0, the default means return all rows).-1all versions
netTimeoutForStreamingResultsWhat value should the driver automatically set the server setting 'net_write_timeout' to when the streaming result sets feature is in use? (value has unit of seconds, the value '0' means the driver will not try and adjust this value)6005.1.0
noAccessToProcedureBodiesWhen determining procedure parameter types for CallableStatements, and the connected user can't access procedure bodies through "SHOW CREATE PROCEDURE" or select on mysql.proc should the driver instead create basic metadata (all parameters reported as IN VARCHARs, but allowing registerOutParameter() to be called on them anyway) instead of throwing an exception?false5.0.3
noDatetimeStringSyncDon't ensure that ResultSet.getDatetimeType().toString().equals(ResultSet.getString())false3.1.7
noTimezoneConversionForTimeTypeDon't convert TIME values using the server timezone if 'useTimezone'='true'false5.0.0
nullCatalogMeansCurrentWhen DatabaseMetadataMethods ask for a 'catalog' parameter, does the value null mean use the current catalog? (this is not JDBC-compliant, but follows legacy behavior from earlier versions of the driver)true3.1.8
nullNamePatternMatchesAllShould DatabaseMetaData methods that accept *pattern parameters treat null the same as '%' (this is not JDBC-compliant, however older versions of the driver accepted this departure from the specification)true3.1.8
overrideSupportsIntegrityEnhancementFacilityShould the driver return "true" for DatabaseMetaData.supportsIntegrityEnhancementFacility() even if the database doesn't support it to workaround applications that require this method to return "true" to signal support of foreign keys, even though the SQL specification states that this facility contains much more than just foreign key support (one such application being OpenOffice)?false3.1.12
padCharsWithSpaceIf a result set column has the CHAR type and the value does not fill the amount of characters specified in the DDL for the column, should the driver pad the remaining characters with space (for ANSI compliance)?false5.0.6
pedanticFollow the JDBC spec to the letter.false3.0.0
pinGlobalTxToPhysicalConnectionWhen using XAConnections, should the driver ensure that operations on a given XID are always routed to the same physical connection? This allows the XAConnection to support "XA START ... JOIN" after "XA END" has been calledfalse5.0.1
populateInsertRowWithDefaultValuesWhen using ResultSets that are CONCUR_UPDATABLE, should the driver pre-populate the "insert" row with default values from the DDL for the table used in the query so those values are immediately available for ResultSet accessors? This functionality requires a call to the database for metadata each time a result set of this type is created. If disabled (the default), the default values will be populated by the an internal call to refreshRow() which pulls back default values and/or values changed by triggers.false5.0.5
processEscapeCodesForPrepStmtsShould the driver process escape codes in queries that are prepared?true3.1.12
relaxAutoCommitIf the version of MySQL the driver connects to does not support transactions, still allow calls to commit(), rollback() and setAutoCommit() (true/false, defaults to 'false')?false2.0.13
retainStatementAfterResultSetCloseShould the driver retain the Statement reference in a ResultSet after ResultSet.close() has been called. This is not JDBC-compliant after JDBC-4.0.false3.1.11
rollbackOnPooledCloseShould the driver issue a rollback() when the logical connection in a pool is closed?true3.0.15
runningCTS13Enables workarounds for bugs in Sun's JDBC compliance testsuite version 1.3false3.1.7
serverTimezoneOverride detection/mapping of timezone. Used when timezone from server doesn't map to Java timezone 3.0.2
statementInterceptorsA comma-delimited list of classes that implement "com.mysql.jdbc.StatementInterceptor" that should be placed "in between" query execution to influence the results. StatementInterceptors are "chainable", the results returned by the "current" interceptor will be passed on to the next in in the chain, from left-to-right order, as specified in this property. 5.1.1
strictFloatingPointUsed only in older versions of compliance testfalse3.0.0
strictUpdatesShould the driver do strict checking (all primary keys selected) of updatable result sets (true, false, defaults to 'true')?true3.0.4
tinyInt1isBitShould the driver treat the datatype TINYINT(1) as the BIT type (because the server silently converts BIT -> TINYINT(1) when creating tables)?true3.0.16
transformedBitIsBooleanIf the driver converts TINYINT(1) to a different type, should it use BOOLEAN instead of BIT for future compatibility with MySQL-5.0, as MySQL-5.0 has a BIT type?false3.1.9
treatUtilDateAsTimestampShould the driver treat java.util.Date as a TIMESTAMP for the purposes of PreparedStatement.setObject()?true5.0.5
ultraDevHackCreate PreparedStatements for prepareCall() when required, because UltraDev is broken and issues a prepareCall() for _all_ statements? (true/false, defaults to 'false')false2.0.3
useGmtMillisForDatetimesConvert between session timezone and GMT before creating Date and Timestamp instances (value of "false" is legacy behavior, "true" leads to more JDBC-compliant behavior.false3.1.12
useHostsInPrivilegesAdd '@hostname' to users in DatabaseMetaData.getColumn/TablePrivileges() (true/false), defaults to 'true'.true3.0.2
useInformationSchemaWhen connected to MySQL-5.0.7 or newer, should the driver use the INFORMATION_SCHEMA to derive information used by DatabaseMetaData?false5.0.0
useJDBCCompliantTimezoneShiftShould the driver use JDBC-compliant rules when converting TIME/TIMESTAMP/DATETIME values' timezone information for those JDBC arguments which take a java.util.Calendar argument? (Notice that this option is exclusive of the "useTimezone=true" configuration option.)false5.0.0
useLegacyDatetimeCodeUse code for DATE/TIME/DATETIME/TIMESTAMP handling in result sets and statements that consistently handles timezone conversions from client to server and back again, or use the legacy code for these datatypes that has been in the driver for backwards-compatibility?true5.1.6
useOldAliasMetadataBehaviorShould the driver use the legacy behavior for "AS" clauses on columns and tables, and only return aliases (if any) for ResultSetMetaData.getColumnName() or ResultSetMetaData.getTableName() rather than the original column/table name? In 5.0.x, the default value was true.false5.0.4
useOldUTF8BehaviorUse the UTF-8 behavior the driver did when communicating with 4.0 and older serversfalse3.1.6
useOnlyServerErrorMessagesDon't prepend 'standard' SQLState error messages to error messages returned by the server.true3.0.15
useSSPSCompatibleTimezoneShiftIf migrating from an environment that was using server-side prepared statements, and the configuration property "useJDBCCompliantTimeZoneShift" set to "true", use compatible behavior when not using server-side prepared statements when sending TIMESTAMP values to the MySQL server.false5.0.5
useServerPrepStmtsUse server-side prepared statements if the server supports them?false3.1.0
useSqlStateCodesUse SQL Standard state codes instead of 'legacy' X/Open/SQL state codes (true/false), default is 'true'true3.1.3
useStreamLengthsInPrepStmtsHonor stream length parameter in PreparedStatement/ResultSet.setXXXStream() method calls (true/false, defaults to 'true')?true3.0.2
useTimezoneConvert time/date types between client and server timezones (true/false, defaults to 'false')?false3.0.2
useUnbufferedInputDon't use BufferedInputStream for reading data from the servertrue3.0.11
yearIsDateTypeShould the JDBC driver treat the MySQL type "YEAR" as a java.sql.Date, or as a SHORT?true3.1.9
zeroDateTimeBehaviorWhat should happen when the driver encounters DATETIME values that are composed entirely of zeroes (used by MySQL to represent invalid dates)? Valid values are "exception", "round" and "convertToNull".exception3.1.4

Connector/J also supports access to MySQL via named pipes on Windows NT/2000/XP using the NamedPipeSocketFactory as a plugin-socket factory via the socketFactory property. If you don't use a namedPipePath property, the default of '\\.\pipe\MySQL' will be used. If you use the NamedPipeSocketFactory, the hostname and port number values in the JDBC url will be ignored. You can enable this feature using:

socketFactory=com.mysql.jdbc.NamedPipeSocketFactory
        

Named pipes only work when connecting to a MySQL server on the same physical machine as the one the JDBC driver is being used on. In simple performance tests, it appears that named pipe access is between 30%-50% faster than the standard TCP/IP access. However, this varies per system, and named pipes are slower than TCP/IP in many Windows configurations.

You can create your own socket factories by following the example code in com.mysql.jdbc.NamedPipeSocketFactory, or com.mysql.jdbc.StandardSocketFactory.

27.4.4.2. JDBC API Implementation Notes

MySQL Connector/J passes all of the tests in the publicly-available version of Sun's JDBC compliance test suite. However, in many places the JDBC specification is vague about how certain functionality should be implemented, or the specification allows leeway in implementation.

This section gives details on a interface-by-interface level about how certain implementation decisions may affect how you use MySQL Connector/J.

  • Blob

    Starting with Connector/J version 3.1.0, you can emulate Blobs with locators by adding the property 'emulateLocators=true' to your JDBC URL. Using this method, the driver will delay loading the actual Blob data until you retrieve the other data and then use retrieval methods (getInputStream(), getBytes(), and so forth) on the blob data stream.

    For this to work, you must use a column alias with the value of the column to the actual name of the Blob, for example:

    SELECT id, 'data' as blob_data from blobtable

    For this to work, you must also follow these rules:

    • The SELECT must also reference only one table, the table must have a primary key.

    • The SELECT must alias the original blob column name, specified as a string, to an alternate name.

    • The SELECT must cover all columns that make up the primary key.

    The Blob implementation does not allow in-place modification (they are copies, as reported by the DatabaseMetaData.locatorsUpdateCopies() method). Because of this, you should use the corresponding PreparedStatement.setBlob() or ResultSet.updateBlob() (in the case of updatable result sets) methods to save changes back to the database.

    MySQL Enterprise MySQL Enterprise subscribers will find more information about type conversion in the Knowledge Base article, Type Conversions Supported by MySQL Connector/J. To subscribe to MySQL Enterprise see http://www.mysql.com/products/enterprise/advisors.html.

  • CallableStatement

    Starting with Connector/J 3.1.1, stored procedures are supported when connecting to MySQL version 5.0 or newer via the CallableStatement interface. Currently, the getParameterMetaData() method of CallableStatement is not supported.

  • Clob

    The Clob implementation does not allow in-place modification (they are copies, as reported by the DatabaseMetaData.locatorsUpdateCopies() method). Because of this, you should use the PreparedStatement.setClob() method to save changes back to the database. The JDBC API does not have a ResultSet.updateClob() method.

  • Connection

    Unlike older versions of MM.MySQL the isClosed() method does not ping the server to determine if it is alive. In accordance with the JDBC specification, it only returns true if closed() has been called on the connection. If you need to determine if the connection is still valid, you should issue a simple query, such as SELECT 1. The driver will throw an exception if the connection is no longer valid.

  • DatabaseMetaData

    Foreign Key information (getImportedKeys()/getExportedKeys() and getCrossReference()) is only available from InnoDB tables. However, the driver uses SHOW CREATE TABLE to retrieve this information, so when other storage engines support foreign keys, the driver will transparently support them as well.

  • PreparedStatement

    PreparedStatements are implemented by the driver, as MySQL does not have a prepared statement feature. Because of this, the driver does not implement getParameterMetaData() or getMetaData() as it would require the driver to have a complete SQL parser in the client.

    Starting with version 3.1.0 MySQL Connector/J, server-side prepared statements and binary-encoded result sets are used when the server supports them.

    Take care when using a server-side prepared statement with large parameters that are set via setBinaryStream(), setAsciiStream(), setUnicodeStream(), setBlob(), or setClob(). If you want to re-execute the statement with any large parameter changed to a non-large parameter, it is necessary to call clearParameters() and set all parameters again. The reason for this is as follows:

    • During both server-side prepared statements and client-side emulation, large data is exchanged only when PreparedStatement.execute() is called.

    • Once that has been done, the stream used to read the data on the client side is closed (as per the JDBC spec), and can't be read from again.

    • If a parameter changes from large to non-large, the driver must reset the server-side state of the prepared statement to allow the parameter that is being changed to take the place of the prior large value. This removes all of the large data that has already been sent to the server, thus requiring the data to be re-sent, via the setBinaryStream(), setAsciiStream(), setUnicodeStream(), setBlob() or setClob() methods.

    Consequently, if you want to change the type of a parameter to a non-large one, you must call clearParameters() and set all parameters of the prepared statement again before it can be re-executed.

  • ResultSet

    By default, ResultSets are completely retrieved and stored in memory. In most cases this is the most efficient way to operate, and due to the design of the MySQL network protocol is easier to implement. If you are working with ResultSets that have a large number of rows or large values, and can not allocate heap space in your JVM for the memory required, you can tell the driver to stream the results back one row at a time.

    To enable this functionality, you need to create a Statement instance in the following manner:

    stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
                  java.sql.ResultSet.CONCUR_READ_ONLY);
    stmt.setFetchSize(Integer.MIN_VALUE);

    The combination of a forward-only, read-only result set, with a fetch size of Integer.MIN_VALUE serves as a signal to the driver to stream result sets row-by-row. After this any result sets created with the statement will be retrieved row-by-row.

    There are some caveats with this approach. You will have to read all of the rows in the result set (or close it) before you can issue any other queries on the connection, or an exception will be thrown.

    The earliest the locks these statements hold can be released (whether they be MyISAM table-level locks or row-level locks in some other storage engine such as InnoDB) is when the statement completes.

    If the statement is within scope of a transaction, then locks are released when the transaction completes (which implies that the statement needs to complete first). As with most other databases, statements are not complete until all the results pending on the statement are read or the active result set for the statement is closed.

    Therefore, if using streaming results, you should process them as quickly as possible if you want to maintain concurrent access to the tables referenced by the statement producing the result set.

  • ResultSetMetaData

    The isAutoIncrement() method only works when using MySQL servers 4.0 and newer.

  • Statement

    When using versions of the JDBC driver earlier than 3.2.1, and connected to server versions earlier than 5.0.3, the setFetchSize() method has no effect, other than to toggle result set streaming as described above.

    Connector/J 5.0.0 and later include support for both Statement.cancel() and Statement.setQueryTimeout(). Both require MySQL 5.0.0 or newer server, and require a separate connection to issue the KILL QUERY statement. In the case of setQueryTimeout(), the implementation creates an additional thread to handle the timeout functionality.

    Note

    Failures to cancel the statement for setQueryTimeout() may manifest themselves as RuntimeException rather than failing silently, as there is currently no way to unblock the thread that is executing the query being cancelled due to timeout expiration and have it throw the exception instead.

    MySQL does not support SQL cursors, and the JDBC driver doesn't emulate them, so "setCursorName()" has no effect.

    Connector/J 5.1.3 and later include two additional methods:

    • setLocalInfileInputStream() sets an InputStream instance that will be used to send data to the MySQL server for a LOAD DATA LOCAL INFILE statement rather than a FileInputStream or URLInputStream that represents the path given as an argument to the statement.

      This stream will be read to completion upon execution of a LOAD DATA LOCAL INFILE statement, and will automatically be closed by the driver, so it needs to be reset before each call to execute*() that would cause the MySQL server to request data to fulfill the request for LOAD DATA LOCAL INFILE.

      If this value is set to NULL, the driver will revert to using a FileInputStream or URLInputStream as required.

    • getLocalInfileInputStream() returns the InputStream instance that will be used to send data in response to a LOAD DATA LOCAL INFILE statement.

      This method returns NULL if no such stream has been set via setLocalInfileInputStream().

27.4.4.3. Java, JDBC and MySQL Types

MySQL Connector/J is flexible in the way it handles conversions between MySQL data types and Java data types.

In general, any MySQL data type can be converted to a java.lang.String, and any numerical type can be converted to any of the Java numerical types, although round-off, overflow, or loss of precision may occur.

Starting with Connector/J 3.1.0, the JDBC driver will issue warnings or throw DataTruncation exceptions as is required by the JDBC specification unless the connection was configured not to do so by using the property jdbcCompliantTruncation and setting it to false.

The conversions that are always guaranteed to work are listed in the following table:

Connection Properties - Miscellaneous. 

These MySQL Data TypesCan always be converted to these Java types
CHAR, VARCHAR, BLOB, TEXT, ENUM, and SETjava.lang.String, java.io.InputStream, java.io.Reader, java.sql.Blob, java.sql.Clob
FLOAT, REAL, DOUBLE PRECISION, NUMERIC, DECIMAL, TINYINT, SMALLINT, MEDIUMINT, INTEGER, BIGINTjava.lang.String, java.lang.Short, java.lang.Integer, java.lang.Long, java.lang.Double, java.math.BigDecimal
DATE, TIME, DATETIME, TIMESTAMPjava.lang.String, java.sql.Date, java.sql.Timestamp

Note

Round-off, overflow or loss of precision may occur if you choose a Java numeric data type that has less precision or capacity than the MySQL data type you are converting to/from.

The ResultSet.getObject() method uses the type conversions between MySQL and Java types, following the JDBC specification where appropriate. The value returned by ResultSetMetaData.GetColumnClassName() is also shown below. For more information on the java.sql.Types classes see Java 2 Platform Types.

MySQL Types to Java Types for ResultSet.getObject(). 

MySQL Type NameReturn value of GetColumnClassNameReturned as Java Class
BIT(1) (new in MySQL-5.0)BITjava.lang.Boolean
BIT( > 1) (new in MySQL-5.0)BITbyte[]
TINYINTTINYINTjava.lang.Boolean if the configuration property tinyInt1isBit is set to true (the default) and the storage size is 1, or java.lang.Integer if not.
BOOL, BOOLEANTINYINTSee TINYINT, above as these are aliases for TINYINT(1), currently.
SMALLINT[(M)] [UNSIGNED]SMALLINT [UNSIGNED]java.lang.Integer (regardless if UNSIGNED or not)
MEDIUMINT[(M)] [UNSIGNED]MEDIUMINT [UNSIGNED]java.lang.Integer, if UNSIGNED java.lang.Long (C/J 3.1 and earlier), or java.lang.Integer for C/J 5.0 and later
INT,INTEGER[(M)] [UNSIGNED]INTEGER [UNSIGNED]java.lang.Integer, if UNSIGNED java.lang.Long
BIGINT[(M)] [UNSIGNED]BIGINT [UNSIGNED]java.lang.Long, if UNSIGNED java.math.BigInteger
FLOAT[(M,D)]FLOATjava.lang.Float
DOUBLE[(M,B)]DOUBLEjava.lang.Double
DECIMAL[(M[,D])]DECIMALjava.math.BigDecimal
DATEDATEjava.sql.Date
DATETIMEDATETIMEjava.sql.Timestamp
TIMESTAMP[(M)]TIMESTAMPjava.sql.Timestamp
TIMETIMEjava.sql.Time
YEAR[(2|4)]YEARIf yearIsDateType configuration property is set to false, then the returned object type is java.sql.Short. If set to true (the default) then an object of type java.sql.Date (with the date set to January 1st, at midnight).
CHAR(M)CHARjava.lang.String (unless the character set for the column is BINARY, then byte[] is returned.
VARCHAR(M) [BINARY]VARCHARjava.lang.String (unless the character set for the column is BINARY, then byte[] is returned.
BINARY(M)BINARYbyte[]
VARBINARY(M)VARBINARYbyte[]
TINYBLOBTINYBLOBbyte[]
TINYTEXTVARCHARjava.lang.String
BLOBBLOBbyte[]
TEXTVARCHARjava.lang.String
MEDIUMBLOBMEDIUMBLOBbyte[]
MEDIUMTEXTVARCHARjava.lang.String
LONGBLOBLONGBLOBbyte[]
LONGTEXTVARCHARjava.lang.String
ENUM('value1','value2',...)CHARjava.lang.String
SET('value1','value2',...)CHARjava.lang.String

27.4.4.4. Using Character Sets and Unicode

All strings sent from the JDBC driver to the server are converted automatically from native Java Unicode form to the client character encoding, including all queries sent via Statement.execute(), Statement.executeUpdate(), Statement.executeQuery() as well as all PreparedStatement and CallableStatement parameters with the exclusion of parameters set using setBytes(), setBinaryStream(), setAsciiStream(), setUnicodeStream() and setBlob().

Prior to MySQL Server 4.1, Connector/J supported a single character encoding per connection, which could either be automatically detected from the server configuration, or could be configured by the user through the useUnicode and characterEncoding properties.

Starting with MySQL Server 4.1, Connector/J supports a single character encoding between client and server, and any number of character encodings for data returned by the server to the client in ResultSets.

The character encoding between client and server is automatically detected upon connection. The encoding used by the driver is specified on the server via the character_set system variable for server versions older than 4.1.0 and character_set_server for server versions 4.1.0 and newer. For more information, see Section 9.1.3.1, “Server Character Set and Collation”.

To override the automatically-detected encoding on the client side, use the characterEncoding property in the URL used to connect to the server.

When specifying character encodings on the client side, Java-style names should be used. The following table lists Java-style names for MySQL character sets:

MySQL to Java Encoding Name Translations. 

MySQL Character Set NameJava-Style Character Encoding Name
asciiUS-ASCII
big5Big5
gbkGBK
sjisSJIS (or Cp932 or MS932 for MySQL Server < 4.1.11)
cp932Cp932 or MS932 (MySQL Server > 4.1.11)
gb2312EUC_CN
ujisEUC_JP
euckrEUC_KR
latin1ISO8859_1
latin2ISO8859_2
greekISO8859_7
hebrewISO8859_8
cp866Cp866
tis620TIS620
cp1250Cp1250
cp1251Cp1251
cp1257Cp1257
macromanMacRoman
macceMacCentralEurope
utf8UTF-8
ucs2UnicodeBig

Warning

Do not issue the query 'set names' with Connector/J, as the driver will not detect that the character set has changed, and will continue to use the character set detected during the initial connection setup.

To allow multiple character sets to be sent from the client, the UTF-8 encoding should be used, either by configuring utf8 as the default server character set, or by configuring the JDBC driver to use UTF-8 through the characterEncoding property.

27.4.4.5. Connecting Securely Using SSL

SSL in MySQL Connector/J encrypts all data (other than the initial handshake) between the JDBC driver and the server. The performance penalty for enabling SSL is an increase in query processing time between 35% and 50%, depending on the size of the query, and the amount of data it returns.

For SSL Support to work, you must have the following:

The system works through two Java truststore files, one file contains the certificate information for the server (truststore in the examples below). The other file contains the certificate for the client (keystore in the examples below). All Java truststore files are password protected by supplying a suitable password to the keytool when you create the files. You need the file names and associated passwords to create an SSL connection.

You will first need to import the MySQL server CA Certificate into a Java truststore. A sample MySQL server CA Certificate is located in the SSL subdirectory of the MySQL source distribution. This is what SSL will use to determine if you are communicating with a secure MySQL server. Alternatively, use the CA Certificate that you have generated or been provided with by your SSL provider.

To use Java's keytool to create a truststore in the current directory , and import the server's CA certificate (cacert.pem), you can do the following (assuming that keytool is in your path. The keytool should be located in the bin subdirectory of your JDK or JRE):

shell> keytool -import -alias mysqlServerCACert \
                                  -file cacert.pem -keystore truststore

You will need to enter the password when prompted for the keystore file. Interaction with keytool will look like this:

Enter keystore password:  *********
Owner: EMAILADDRESS=walrus@example.com, CN=Walrus, 
       O=MySQL AB, L=Orenburg, ST=Some-State, C=RU
Issuer: EMAILADDRESS=walrus@example.com, CN=Walrus, 
       O=MySQL AB, L=Orenburg, ST=Some-State, C=RU
Serial number: 0
Valid from: 
   Fri Aug 02 16:55:53 CDT 2002 until: Sat Aug 02 16:55:53 CDT 2003
Certificate fingerprints:
    MD5:  61:91:A0:F2:03:07:61:7A:81:38:66:DA:19:C4:8D:AB
    SHA1: 25:77:41:05:D5:AD:99:8C:14:8C:CA:68:9C:2F:B8:89:C3:34:4D:6C
Trust this certificate? [no]:  yes
Certificate was added to keystore

You then have two options, you can either import the client certificate that matches the CA certificate you just imported, or you can create a new client certificate.

To import an existing certificate, the certificate should be in DER format. You can use openssl to convert an existing certificate into the new format. For example:

shell> openssl x509 -outform DER -in client-cert.pem -out client.cert
      

You now need to import the converted certificate into your keystore using keytool:

shell> keytool -import -file client.cert -keystore keystore -alias mysqlClientCertificate

To generate your own client certificate, use keytool to create a suitable certificate and add it to the keystore file:

 shell> keytool -genkey -keyalg rsa \
     -alias mysqlClientCertificate -keystore keystore 

Keytool will prompt you for the following information, and create a keystore named keystore in the current directory.

You should respond with information that is appropriate for your situation:

Enter keystore password:  *********
What is your first and last name?
  [Unknown]:  Matthews
What is the name of your organizational unit?
  [Unknown]:  Software Development
What is the name of your organization?
  [Unknown]:  MySQL AB
What is the name of your City or Locality?
  [Unknown]:  Flossmoor
What is the name of your State or Province?
  [Unknown]:  IL
What is the two-letter country code for this unit?
  [Unknown]:  US
Is <CN=Matthews, OU=Software Development, O=MySQL AB,
 L=Flossmoor, ST=IL, C=US> correct?
  [no]:  y

Enter key password for <mysqlClientCertificate>
        (RETURN if same as keystore password):

Finally, to get JSSE to use the keystore and truststore that you have generated, you need to set the following system properties when you start your JVM, replacing path_to_keystore_file with the full path to the keystore file you created, path_to_truststore_file with the path to the truststore file you created, and using the appropriate password values for each property. You can do this either on the command line:

-Djavax.net.ssl.keyStore=path_to_keystore_file
-Djavax.net.ssl.keyStorePassword=password
-Djavax.net.ssl.trustStore=path_to_truststore_file
-Djavax.net.ssl.trustStorePassword=password 

Or you can set the values directly within the application:

 System.setProperty("javax.net.ssl.keyStore","path_to_keystore_file");
System.setProperty("javax.net.ssl.keyStorePassword","password");
System.setProperty("javax.net.ssl.trustStore","path_to_truststore_file");
System.setProperty("javax.net.ssl.trustStorePassword","password");

You will also need to set useSSL to true in your connection parameters for MySQL Connector/J, either by adding useSSL=true to your URL, or by setting the property useSSL to true in the java.util.Properties instance you pass to DriverManager.getConnection().

You can test that SSL is working by turning on JSSE debugging (as detailed below), and look for the following key events:

...
*** ClientHello, v3.1
RandomCookie:  GMT: 1018531834 bytes = { 199, 148, 180, 215, 74, 12, »
  54, 244, 0, 168, 55, 103, 215, 64, 16, 138, 225, 190, 132, 153, 2, »
  217, 219, 239, 202, 19, 121, 78 }
Session ID:  {}
Cipher Suites:  { 0, 5, 0, 4, 0, 9, 0, 10, 0, 18, 0, 19, 0, 3, 0, 17 }
Compression Methods:  { 0 }
***
[write] MD5 and SHA1 hashes:  len = 59
0000: 01 00 00 37 03 01 3D B6 90 FA C7 94 B4 D7 4A 0C  ...7..=.......J.
0010: 36 F4 00 A8 37 67 D7 40 10 8A E1 BE 84 99 02 D9  6...7g.@........
0020: DB EF CA 13 79 4E 00 00 10 00 05 00 04 00 09 00  ....yN..........
0030: 0A 00 12 00 13 00 03 00 11 01 00                 ...........
main, WRITE:  SSL v3.1 Handshake, length = 59
main, READ:  SSL v3.1 Handshake, length = 74
*** ServerHello, v3.1
RandomCookie:  GMT: 1018577560 bytes = { 116, 50, 4, 103, 25, 100, 58, »
   202, 79, 185, 178, 100, 215, 66, 254, 21, 83, 187, 190, 42, 170, 3, »
   132, 110, 82, 148, 160, 92 }
Session ID:  {163, 227, 84, 53, 81, 127, 252, 254, 178, 179, 68, 63, »
   182, 158, 30, 11, 150, 79, 170, 76, 255, 92, 15, 226, 24, 17, 177, »
   219, 158, 177, 187, 143}
Cipher Suite:  { 0, 5 }
Compression Method: 0
***
%% Created:  [Session-1, SSL_RSA_WITH_RC4_128_SHA]
** SSL_RSA_WITH_RC4_128_SHA
[read] MD5 and SHA1 hashes:  len = 74
0000: 02 00 00 46 03 01 3D B6 43 98 74 32 04 67 19 64  ...F..=.C.t2.g.d
0010: 3A CA 4F B9 B2 64 D7 42 FE 15 53 BB BE 2A AA 03  :.O..d.B..S..*..
0020: 84 6E 52 94 A0 5C 20 A3 E3 54 35 51 7F FC FE B2  .nR..\ ..T5Q....
0030: B3 44 3F B6 9E 1E 0B 96 4F AA 4C FF 5C 0F E2 18  .D?.....O.L.\...
0040: 11 B1 DB 9E B1 BB 8F 00 05 00                    ..........
main, READ:  SSL v3.1 Handshake, length = 1712
...

JSSE provides debugging (to STDOUT) when you set the following system property: -Djavax.net.debug=all This will tell you what keystores and truststores are being used, as well as what is going on during the SSL handshake and certificate exchange. It will be helpful when trying to determine what is not working when trying to get an SSL connection to happen.

27.4.4.6. Using Master/Slave Replication with ReplicationConnection

Starting with Connector/J 3.1.7, we've made available a variant of the driver that will automatically send queries to a read/write master, or a failover or round-robin loadbalanced set of slaves based on the state of Connection.getReadOnly() .

An application signals that it wants a transaction to be read-only by calling Connection.setReadOnly(true), this replication-aware connection will use one of the slave connections, which are load-balanced per-vm using a round-robin scheme (a given connection is sticky to a slave unless that slave is removed from service). If you have a write transaction, or if you have a read that is time-sensitive (remember, replication in MySQL is asynchronous), set the connection to be not read-only, by calling Connection.setReadOnly(false) and the driver will ensure that further calls are sent to the master MySQL server. The driver takes care of propagating the current state of autocommit, isolation level, and catalog between all of the connections that it uses to accomplish this load balancing functionality.

To enable this functionality, use the " com.mysql.jdbc.ReplicationDriver " class when configuring your application server's connection pool or when creating an instance of a JDBC driver for your standalone application. Because it accepts the same URL format as the standard MySQL JDBC driver, ReplicationDriver does not currently work with java.sql.DriverManager -based connection creation unless it is the only MySQL JDBC driver registered with the DriverManager .

Here is a short, simple example of how ReplicationDriver might be used in a standalone application.

import java.sql.Connection;
import java.sql.ResultSet;
import java.util.Properties;

import com.mysql.jdbc.ReplicationDriver;

public class ReplicationDriverDemo {

  public static void main(String[] args) throws Exception {
    ReplicationDriver driver = new ReplicationDriver();

    Properties props = new Properties();

    // We want this for failover on the slaves
    props.put("autoReconnect", "true");

    // We want to load balance between the slaves
    props.put("roundRobinLoadBalance", "true");

    props.put("user", "foo");
    props.put("password", "bar");

    //
    // Looks like a normal MySQL JDBC url, with a
    // comma-separated list of hosts, the first 
    // being the 'master', the rest being any number
    // of slaves that the driver will load balance against
    //

    Connection conn =
        driver.connect("jdbc:mysql://master,slave1,slave2,slave3/test",
            props);

    //
    // Perform read/write work on the master
    // by setting the read-only flag to "false"
    //

    conn.setReadOnly(false);
    conn.setAutoCommit(false);
    conn.createStatement().executeUpdate("UPDATE some_table ....");
    conn.commit();

    //
    // Now, do a query from a slave, the driver automatically picks one
    // from the list
    //

    conn.setReadOnly(true);

    ResultSet rs = 
      conn.createStatement().executeQuery("SELECT a,b FROM alt_table");

     .......
  }
}

You may also want to investigate the Load Balancing JDBC Pool (lbpol) tool, which provides a wrapper around the standard JDBC driver and allows you to use DB connection pools that includes checks for system failures and uneven load distribution. For more information, see Load Balancing JDBC Pool (lbpool).

27.4.4.7. Mapping MySQL Error Numbers to SQLStates

The table below provides a mapping of the MySQL Error Numbers to SQL States

Table 27.1. Mapping of MySQL Error Numbers to SQLStates

MySQL Error NumberMySQL Error NameLegacy (X/Open) SQLStateSQL Standard SQLState
1022ER_DUP_KEYS100023000
1037ER_OUTOFMEMORYS1001HY001
1038ER_OUT_OF_SORTMEMORYS1001HY001
1040ER_CON_COUNT_ERROR0800408004
1042ER_BAD_HOST_ERROR0800408S01
1043ER_HANDSHAKE_ERROR0800408S01
1044ER_DBACCESS_DENIED_ERRORS100042000
1045ER_ACCESS_DENIED_ERROR2800028000
1047ER_UNKNOWN_COM_ERROR08S01HY000
1050ER_TABLE_EXISTS_ERRORS100042S01
1051ER_BAD_TABLE_ERROR42S0242S02
1052ER_NON_UNIQ_ERRORS100023000
1053ER_SERVER_SHUTDOWNS100008S01
1054ER_BAD_FIELD_ERRORS002242S22
1055ER_WRONG_FIELD_WITH_GROUPS100942000
1056ER_WRONG_GROUP_FIELDS100942000
1057ER_WRONG_SUM_SELECTS100942000
1058ER_WRONG_VALUE_COUNT21S0121S01
1059ER_TOO_LONG_IDENTS100942000
1060ER_DUP_FIELDNAMES100942S21
1061ER_DUP_KEYNAMES100942000
1062ER_DUP_ENTRYS100923000
1063ER_WRONG_FIELD_SPECS100942000
1064ER_PARSE_ERROR4200042000
1065ER_EMPTY_QUERY4200042000
1066ER_NONUNIQ_TABLES100942000
1067ER_INVALID_DEFAULTS100942000
1068ER_MULTIPLE_PRI_KEYS100942000
1069ER_TOO_MANY_KEYSS100942000
1070ER_TOO_MANY_KEY_PARTSS100942000
1071ER_TOO_LONG_KEYS100942000
1072ER_KEY_COLUMN_DOES_NOT_EXITSS100942000
1073ER_BLOB_USED_AS_KEYS100942000
1074ER_TOO_BIG_FIELDLENGTHS100942000
1075ER_WRONG_AUTO_KEYS100942000
1080ER_FORCING_CLOSES100008S01
1081ER_IPSOCK_ERROR08S0108S01
1082ER_NO_SUCH_INDEXS100942S12
1083ER_WRONG_FIELD_TERMINATORSS100942000
1084ER_BLOBS_AND_NO_TERMINATEDS100942000
1090ER_CANT_REMOVE_ALL_FIELDSS100042000
1091ER_CANT_DROP_FIELD_OR_KEYS100042000
1101ER_BLOB_CANT_HAVE_DEFAULTS100042000
1102ER_WRONG_DB_NAMES100042000
1103ER_WRONG_TABLE_NAMES100042000
1104ER_TOO_BIG_SELECTS100042000
1106ER_UNKNOWN_PROCEDURES100042000
1107ER_WRONG_PARAMCOUNT_TO_PROCEDURES100042000
1109ER_UNKNOWN_TABLES100042S02
1110ER_FIELD_SPECIFIED_TWICES100042000
1112ER_UNSUPPORTED_EXTENSIONS100042000
1113ER_TABLE_MUST_HAVE_COLUMNSS100042000
1115ER_UNKNOWN_CHARACTER_SETS100042000
1118ER_TOO_BIG_ROWSIZES100042000
1120ER_WRONG_OUTER_JOINS100042000
1121ER_NULL_COLUMN_IN_INDEXS100042000
1129ER_HOST_IS_BLOCKED08004HY000
1130ER_HOST_NOT_PRIVILEGED08004HY000
1131ER_PASSWORD_ANONYMOUS_USERS100042000
1132ER_PASSWORD_NOT_ALLOWEDS100042000
1133ER_PASSWORD_NO_MATCHS100042000
1136ER_WRONG_VALUE_COUNT_ON_ROWS100021S01
1138ER_INVALID_USE_OF_NULLS100042000
1139ER_REGEXP_ERRORS100042000
1140ER_MIX_OF_GROUP_FUNC_AND_FIELDSS100042000
1141ER_NONEXISTING_GRANTS100042000
1142ER_TABLEACCESS_DENIED_ERRORS100042000
1143ER_COLUMNACCESS_DENIED_ERRORS100042000
1144ER_ILLEGAL_GRANT_FOR_TABLES100042000
1145ER_GRANT_WRONG_HOST_OR_USERS100042000
1146ER_NO_SUCH_TABLES100042S02
1147ER_NONEXISTING_TABLE_GRANTS100042000
1148ER_NOT_ALLOWED_COMMANDS100042000
1149ER_SYNTAX_ERRORS100042000
1152ER_ABORTING_CONNECTIONS100008S01
1153ER_NET_PACKET_TOO_LARGES100008S01
1154ER_NET_READ_ERROR_FROM_PIPES100008S01
1155ER_NET_FCNTL_ERRORS100008S01
1156ER_NET_PACKETS_OUT_OF_ORDERS100008S01
1157ER_NET_UNCOMPRESS_ERRORS100008S01
1158ER_NET_READ_ERRORS100008S01
1159ER_NET_READ_INTERRUPTEDS100008S01
1160ER_NET_ERROR_ON_WRITES100008S01
1161ER_NET_WRITE_INTERRUPTEDS100008S01
1162ER_TOO_LONG_STRINGS100042000
1163ER_TABLE_CANT_HANDLE_BLOBS100042000
1164ER_TABLE_CANT_HANDLE_AUTO_INCREMENTS100042000
1166ER_WRONG_COLUMN_NAMES100042000
1167ER_WRONG_KEY_COLUMNS100042000
1169ER_DUP_UNIQUES100023000
1170ER_BLOB_KEY_WITHOUT_LENGTHS100042000
1171ER_PRIMARY_CANT_HAVE_NULLS100042000
1172ER_TOO_MANY_ROWSS100042000
1173ER_REQUIRES_PRIMARY_KEYS100042000
1177ER_CHECK_NO_SUCH_TABLES100042000
1178ER_CHECK_NOT_IMPLEMENTEDS100042000
1179ER_CANT_DO_THIS_DURING_AN_TRANSACTIONS100025000
1184ER_NEW_ABORTING_CONNECTIONS100008S01
1189ER_MASTER_NET_READS100008S01
1190ER_MASTER_NET_WRITES100008S01
1203ER_TOO_MANY_USER_CONNECTIONSS100042000
1205ER_LOCK_WAIT_TIMEOUT4100041000
1207ER_READ_ONLY_TRANSACTIONS100025000
1211ER_NO_PERMISSION_TO_CREATE_USERS100042000
1213ER_LOCK_DEADLOCK4100040001
1216ER_NO_REFERENCED_ROWS100023000
1217ER_ROW_IS_REFERENCEDS100023000
1218ER_CONNECT_TO_MASTERS100008S01
1222ER_WRONG_NUMBER_OF_COLUMNS_IN_SELECTS100021000
1226ER_USER_LIMIT_REACHEDS100042000
1230ER_NO_DEFAULTS100042000
1231ER_WRONG_VALUE_FOR_VARS100042000
1232ER_WRONG_TYPE_FOR_VARS100042000
1234ER_CANT_USE_OPTION_HERES100042000
1235ER_NOT_SUPPORTED_YETS100042000
1239ER_WRONG_FK_DEFS100042000
1241ER_OPERAND_COLUMNSS100021000
1242ER_SUBQUERY_NO_1_ROWS100021000
1247ER_ILLEGAL_REFERENCES100042S22
1248ER_DERIVED_MUST_HAVE_ALIASS100042000
1249ER_SELECT_REDUCEDS100001000
1250ER_TABLENAME_NOT_ALLOWED_HERES100042000
1251ER_NOT_SUPPORTED_AUTH_MODES100008004
1252ER_SPATIAL_CANT_HAVE_NULLS100042000
1253ER_COLLATION_CHARSET_MISMATCHS100042000
1261ER_WARN_TOO_FEW_RECORDSS100001000
1262ER_WARN_TOO_MANY_RECORDSS100001000
1263ER_WARN_NULL_TO_NOTNULLS100001000
1264ER_WARN_DATA_OUT_OF_RANGES100001000
1265ER_WARN_DATA_TRUNCATEDS100001000
1280ER_WRONG_NAME_FOR_INDEXS100042000
1281ER_WRONG_NAME_FOR_CATALOGS100042000
1286ER_UNKNOWN_STORAGE_ENGINES100042000

27.4.5. Connector/J Notes and Tips

27.4.5.1. Basic JDBC Concepts

This section provides some general JDBC background.

27.4.5.1.1. Connecting to MySQL Using the DriverManager Interface

When you are using JDBC outside of an application server, the DriverManager class manages the establishment of Connections.

The DriverManager needs to be told which JDBC drivers it should try to make Connections with. The easiest way to do this is to use Class.forName() on the class that implements the java.sql.Driver interface. With MySQL Connector/J, the name of this class is com.mysql.jdbc.Driver. With this method, you could use an external configuration file to supply the driver class name and driver parameters to use when connecting to a database.

The following section of Java code shows how you might register MySQL Connector/J from the main() method of your application:

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

// Notice, do not import com.mysql.jdbc.*
// or you will have problems!

public class LoadDriver {
    public static void main(String[] args) {
        try {
            // The newInstance() call is a work around for some
            // broken Java implementations

            Class.forName("com.mysql.jdbc.Driver").newInstance();
        } catch (Exception ex) {
            // handle the error
        }
    }    
}

After the driver has been registered with the DriverManager, you can obtain a Connection instance that is connected to a particular database by calling DriverManager.getConnection():

Example 27.1. Obtaining a connection from the DriverManager

This example shows how you can obtain a Connection instance from the DriverManager. There are a few different signatures for the getConnection() method. You should see the API documentation that comes with your JDK for more specific information on how to use them.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

Connection conn = null;
...
try {
    conn = 
       DriverManager.getConnection("jdbc:mysql://localhost/test?" + 
                                   "user=monty&password=greatsqldb");

    // Do something with the Connection

   ...
} catch (SQLException ex) {
    // handle any errors
    System.out.println("SQLException: " + ex.getMessage());
    System.out.println("SQLState: " + ex.getSQLState());
    System.out.println("VendorError: " + ex.getErrorCode());
}

Once a Connection is established, it can be used to create Statement and PreparedStatement objects, as well as retrieve metadata about the database. This is explained in the following sections.

27.4.5.1.2. Using Statements to Execute SQL

Statement objects allow you to execute basic SQL queries and retrieve the results through the ResultSet class which is described later.

To create a Statement instance, you call the createStatement() method on the Connection object you have retrieved via one of the DriverManager.getConnection() or DataSource.getConnection() methods described earlier.

Once you have a Statement instance, you can execute a SELECT query by calling the executeQuery(String) method with the SQL you want to use.

To update data in the database, use the executeUpdate(String SQL) method. This method returns the number of rows affected by the update statement.

If you don't know ahead of time whether the SQL statement will be a SELECT or an UPDATE/INSERT, then you can use the execute(String SQL) method. This method will return true if the SQL query was a SELECT, or false if it was an UPDATE, INSERT, or DELETE statement. If the statement was a SELECT query, you can retrieve the results by calling the getResultSet() method. If the statement was an UPDATE, INSERT, or DELETE statement, you can retrieve the affected rows count by calling getUpdateCount() on the Statement instance.

Example 27.2. Using java.sql.Statement to execute a SELECT query

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.ResultSet;

// assume that conn is an already created JDBC connection (see previous examples)

Statement stmt = null;
ResultSet rs = null;

try {
    stmt = conn.createStatement();
    rs = stmt.executeQuery("SELECT foo FROM bar");

    // or alternatively, if you don't know ahead of time that
    // the query will be a SELECT...

    if (stmt.execute("SELECT foo FROM bar")) {
        rs = stmt.getResultSet();
    }

    // Now do something with the ResultSet ....
}
catch (SQLException ex){
    // handle any errors
    System.out.println("SQLException: " + ex.getMessage());
    System.out.println("SQLState: " + ex.getSQLState());
    System.out.println("VendorError: " + ex.getErrorCode());
}
finally {
    // it is a good idea to release
    // resources in a finally{} block
    // in reverse-order of their creation
    // if they are no-longer needed

    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException sqlEx) { } // ignore 

        rs = null;
    }

    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException sqlEx) { } // ignore

        stmt = null;
    }
}
27.4.5.1.3. Using CallableStatements to Execute Stored Procedures

Starting with MySQL server version 5.0 when used with Connector/J 3.1.1 or newer, the java.sql.CallableStatement interface is fully implemented with the exception of the getParameterMetaData() method.

For more information on MySQL stored procedures, please refer to http://dev.mysql.com/doc/mysql/en/stored-procedures.html.

Connector/J exposes stored procedure functionality through JDBC's CallableStatement interface.

Note

Current versions of MySQL server do not return enough information for the JDBC driver to provide result set metadata for callable statements. This means that when using CallableStatement, ResultSetMetaData may return NULL.

The following example shows a stored procedure that returns the value of inOutParam incremented by 1, and the string passed in via inputParam as a ResultSet:

Example 27.3. Stored Procedures

CREATE PROCEDURE demoSp(IN inputParam VARCHAR(255), \ 
                                        INOUT inOutParam INT)
BEGIN
    DECLARE z INT;
    SET z = inOutParam + 1;
    SET inOutParam = z;

    SELECT inputParam;

    SELECT CONCAT('zyxw', inputParam);
END

To use the demoSp procedure with Connector/J, follow these steps:

  1. Prepare the callable statement by using Connection.prepareCall() .

    Notice that you have to use JDBC escape syntax, and that the parentheses surrounding the parameter placeholders are not optional:

    Example 27.4. Using Connection.prepareCall()

    import java.sql.CallableStatement;
    
    ...
    
        //
        // Prepare a call to the stored procedure 'demoSp'
        // with two parameters
        //
        // Notice the use of JDBC-escape syntax ({call ...})
        //
    
        CallableStatement cStmt = conn.prepareCall("{call demoSp(?, ?)}");
    
    
    
        cStmt.setString(1, "abcdefg");

    Note

    Connection.prepareCall() is an expensive method, due to the metadata retrieval that the driver performs to support output parameters. For performance reasons, you should try to minimize unnecessary calls to Connection.prepareCall() by reusing CallableStatement instances in your code.

  2. Register the output parameters (if any exist)

    To retrieve the values of output parameters (parameters specified as OUT or INOUT when you created the stored procedure), JDBC requires that they be specified before statement execution using the various registerOutputParameter() methods in the CallableStatement interface:

    Example 27.5. Registering output parameters

    import java.sql.Types;
    ...
    //
    // Connector/J supports both named and indexed
    // output parameters. You can register output
    // parameters using either method, as well
    // as retrieve output parameters using either
    // method, regardless of what method was
    // used to register them.
    //
    // The following examples show how to use
    // the various methods of registering
    // output parameters (you should of course
    // use only one registration per parameter).
    //
    
    //
    // Registers the second parameter as output, and
    // uses the type 'INTEGER' for values returned from
    // getObject()
    //
    
    cStmt.registerOutParameter(2, Types.INTEGER);
    
    //
    // Registers the named parameter 'inOutParam', and
    // uses the type 'INTEGER' for values returned from
    // getObject()
    //
    
    cStmt.registerOutParameter("inOutParam", Types.INTEGER);
    ...
    

  3. Set the input parameters (if any exist)

    Input and in/out parameters are set as for PreparedStatement objects. However, CallableStatement also supports setting parameters by name:

    Example 27.6. Setting CallableStatement input parameters

    ...
    
        //
        // Set a parameter by index
        //
    
        cStmt.setString(1, "abcdefg");
    
        //
        // Alternatively, set a parameter using
        // the parameter name
        //
    
        cStmt.setString("inputParameter", "abcdefg");
    
        //
        // Set the 'in/out' parameter using an index
        //
    
        cStmt.setInt(2, 1);
    
        //
        // Alternatively, set the 'in/out' parameter
        // by name
        //
    
        cStmt.setInt("inOutParam", 1);
    
    ...

  4. Execute the CallableStatement, and retrieve any result sets or output parameters.

    Although CallableStatement supports calling any of the Statement execute methods (executeUpdate(), executeQuery() or execute()), the most flexible method to call is execute(), as you do not need to know ahead of time if the stored procedure returns result sets:

    Example 27.7. Retrieving results and output parameter values

    ...
    
        boolean hadResults = cStmt.execute();
    
        //
        // Process all returned result sets
        //
    
        while (hadResults) {
            ResultSet rs = cStmt.getResultSet();
    
            // process result set
            ...
    
            hadResults = cStmt.getMoreResults();
        }
    
        //
        // Retrieve output parameters
        //
        // Connector/J supports both index-based and
        // name-based retrieval
        //
    
        int outputValue = cStmt.getInt(2); // index-based
    
        outputValue = cStmt.getInt("inOutParam"); // name-based
    
    ...

27.4.5.1.4. Retrieving AUTO_INCREMENT Column Values

Before version 3.0 of the JDBC API, there was no standard way of retrieving key values from databases that supported auto increment or identity columns. With older JDBC drivers for MySQL, you could always use a MySQL-specific method on the Statement interface, or issue the query SELECT LAST_INSERT_ID() after issuing an INSERT to a table that had an AUTO_INCREMENT key. Using the MySQL-specific method call isn't portable, and issuing a SELECT to get the AUTO_INCREMENT key's value requires another round-trip to the database, which isn't as efficient as possible. The following code snippets demonstrate the three different ways to retrieve AUTO_INCREMENT values. First, we demonstrate the use of the new JDBC-3.0 method getGeneratedKeys() which is now the preferred method to use if you need to retrieve AUTO_INCREMENT keys and have access to JDBC-3.0. The second example shows how you can retrieve the same value using a standard SELECT LAST_INSERT_ID() query. The final example shows how updatable result sets can retrieve the AUTO_INCREMENT value when using the insertRow() method.

Example 27.8. Retrieving AUTO_INCREMENT column values using Statement.getGeneratedKeys()

   Statement stmt = null;
   ResultSet rs = null;

   try {

    //
    // Create a Statement instance that we can use for
    // 'normal' result sets assuming you have a
    // Connection 'conn' to a MySQL database already
    // available

    stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
                                java.sql.ResultSet.CONCUR_UPDATABLE);

    //
    // Issue the DDL queries for the table for this example
    //

    stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
    stmt.executeUpdate(
            "CREATE TABLE autoIncTutorial ("
            + "priKey INT NOT NULL AUTO_INCREMENT, "
            + "dataField VARCHAR(64), PRIMARY KEY (priKey))");

    //
    // Insert one row that will generate an AUTO INCREMENT
    // key in the 'priKey' field
    //

    stmt.executeUpdate(
            "INSERT INTO autoIncTutorial (dataField) "
            + "values ('Can I Get the Auto Increment Field?')",
            Statement.RETURN_GENERATED_KEYS);

    //
    // Example of using Statement.getGeneratedKeys()
    // to retrieve the value of an auto-increment
    // value
    //

    int autoIncKeyFromApi = -1;

    rs = stmt.getGeneratedKeys();

    if (rs.next()) {
        autoIncKeyFromApi = rs.getInt(1);
    } else {

        // throw an exception from here
    }

    rs.close();

    rs = null;

    System.out.println("Key returned from getGeneratedKeys():"
        + autoIncKeyFromApi);
} finally {

    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException ex) {
            // ignore
        }
    }

    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
}

Example 27.9. Retrieving AUTO_INCREMENT column values using SELECT LAST_INSERT_ID()

   Statement stmt = null;
   ResultSet rs = null;

   try {

    //
    // Create a Statement instance that we can use for
    // 'normal' result sets.

    stmt = conn.createStatement();

    //
    // Issue the DDL queries for the table for this example
    //

    stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
    stmt.executeUpdate(
            "CREATE TABLE autoIncTutorial ("
            + "priKey INT NOT NULL AUTO_INCREMENT, "
            + "dataField VARCHAR(64), PRIMARY KEY (priKey))");

    //
    // Insert one row that will generate an AUTO INCREMENT
    // key in the 'priKey' field
    //

    stmt.executeUpdate(
            "INSERT INTO autoIncTutorial (dataField) "
            + "values ('Can I Get the Auto Increment Field?')");

    //
    // Use the MySQL LAST_INSERT_ID()
    // function to do the same thing as getGeneratedKeys()
    //

    int autoIncKeyFromFunc = -1;
    rs = stmt.executeQuery("SELECT LAST_INSERT_ID()");

    if (rs.next()) {
        autoIncKeyFromFunc = rs.getInt(1);
    } else {
        // throw an exception from here
    }

    rs.close();

    System.out.println("Key returned from " + 
                       "'SELECT LAST_INSERT_ID()': " +
                       autoIncKeyFromFunc);

} finally {

    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException ex) {
            // ignore
        }
    }

    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
}
   

Example 27.10. Retrieving AUTO_INCREMENT column values in Updatable ResultSets

   Statement stmt = null;
   ResultSet rs = null;

   try {

    //
    // Create a Statement instance that we can use for
    // 'normal' result sets as well as an 'updatable'
    // one, assuming you have a Connection 'conn' to
    // a MySQL database already available
    //

    stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
                                java.sql.ResultSet.CONCUR_UPDATABLE);

    //
    // Issue the DDL queries for the table for this example
    //

    stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
    stmt.executeUpdate(
            "CREATE TABLE autoIncTutorial ("
            + "priKey INT NOT NULL AUTO_INCREMENT, "
            + "dataField VARCHAR(64), PRIMARY KEY (priKey))");

    //
    // Example of retrieving an AUTO INCREMENT key
    // from an updatable result set
    //

    rs = stmt.executeQuery("SELECT priKey, dataField "
       + "FROM autoIncTutorial");

    rs.moveToInsertRow();

    rs.updateString("dataField", "AUTO INCREMENT here?");
    rs.insertRow();

    //
    // the driver adds rows at the end
    //

    rs.last();

    //
    // We should now be on the row we just inserted
    //

    int autoIncKeyFromRS = rs.getInt("priKey");

    rs.close();

    rs = null;

    System.out.println("Key returned for inserted row: "
        + autoIncKeyFromRS);

} finally {

    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException ex) {
            // ignore
        }
    }

    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
}


   

When you run the preceding example code, you should get the following output: Key returned from getGeneratedKeys(): 1 Key returned from SELECT LAST_INSERT_ID(): 1 Key returned for inserted row: 2 You should be aware, that at times, it can be tricky to use the SELECT LAST_INSERT_ID() query, as that function's value is scoped to a connection. So, if some other query happens on the same connection, the value will be overwritten. On the other hand, the getGeneratedKeys() method is scoped by the Statement instance, so it can be used even if other queries happen on the same connection, but not on the same Statement instance.

27.4.5.2. Using Connector/J with J2EE and Other Java Frameworks

This section describes how to use Connector/J in several contexts.

27.4.5.2.1. General J2EE Concepts

This section provides general background on J2EE concepts that pertain to use of Connector/J.

27.4.5.2.1.1. Understanding Connection Pooling

Connection pooling is a technique of creating and managing a pool of connections that are ready for use by any thread that needs them.

This technique of pooling connections is based on the fact that most applications only need a thread to have access to a JDBC connection when they are actively processing a transaction, which usually take only milliseconds to complete. When not processing a transaction, the connection would otherwise sit idle. Instead, connection pooling allows the idle connection to be used by some other thread to do useful work.

In practice, when a thread needs to do work against a MySQL or other database with JDBC, it requests a connection from the pool. When the thread is finished using the connection, it returns it to the pool, so that it may be used by any other threads that want to use it.

When the connection is loaned out from the pool, it is used exclusively by the thread that requested it. From a programming point of view, it is the same as if your thread called DriverManager.getConnection() every time it needed a JDBC connection, however with connection pooling, your thread may end up using either a new, or already-existing connection.

Connection pooling can greatly increase the performance of your Java application, while reducing overall resource usage. The main benefits to connection pooling are:

  • Reduced connection creation time

    Although this is not usually an issue with the quick connection setup that MySQL offers compared to other databases, creating new JDBC connections still incurs networking and JDBC driver overhead that will be avoided if connections are recycled.

  • Simplified programming model

    When using connection pooling, each individual thread can act as though it has created its own JDBC connection, allowing you to use straight-forward JDBC programming techniques.

  • Controlled resource usage

    If you don't use connection pooling, and instead create a new connection every time a thread needs one, your application's resource usage can be quite wasteful and lead to unpredictable behavior under load.

Remember that each connection to MySQL has overhead (memory, CPU, context switches, and so forth) on both the client and server side. Every connection limits how many resources there are available to your application as well as the MySQL server. Many of these resources will be used whether or not the connection is actually doing any useful work!

Connection pools can be tuned to maximize performance, while keeping resource utilization below the point where your application will start to fail rather than just run slower.

Luckily, Sun has standardized the concept of connection pooling in JDBC through the JDBC-2.0 Optional interfaces, and all major application servers have implementations of these APIs that work fine with MySQL Connector/J.

Generally, you configure a connection pool in your application server configuration files, and access it via the Java Naming and Directory Interface (JNDI). The following code shows how you might use a connection pool from an application deployed in a J2EE application server:

Example 27.11. Using a connection pool with a J2EE application server

import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;

import javax.naming.InitialContext;
import javax.sql.DataSource;


public class MyServletJspOrEjb {

    public void doSomething() throws Exception {
        /*
         * Create a JNDI Initial context to be able to
         *  lookup  the DataSource
         *
         * In production-level code, this should be cached as
         * an instance or static variable, as it can
         * be quite expensive to create a JNDI context.
         *
         * Note: This code only works when you are using servlets
         * or EJBs in a J2EE application server. If you are
         * using connection pooling in standalone Java code, you
         * will have to create/configure datasources using whatever
         * mechanisms your particular connection pooling library
         * provides.
         */

        InitialContext ctx = new InitialContext();

         /*
          * Lookup the DataSource, which will be backed by a pool
          * that the application server provides. DataSource instances
          * are also a good candidate for caching as an instance
          * variable, as JNDI lookups can be expensive as well.
          */

        DataSource ds = 
          (DataSource)ctx.lookup("java:comp/env/jdbc/MySQLDB");

        /*
         * The following code is what would actually be in your
         * Servlet, JSP or EJB 'service' method...where you need
         * to work with a JDBC connection.
         */

        Connection conn = null;
        Statement stmt = null;

        try {
            conn = ds.getConnection();

            /*
             * Now, use normal JDBC programming to work with
             * MySQL, making sure to close each resource when you're
             * finished with it, which allows the connection pool
             * resources to be recovered as quickly as possible
             */

            stmt = conn.createStatement();
            stmt.execute("SOME SQL QUERY");

            stmt.close();
            stmt = null;

            conn.close();
            conn = null;
        } finally {
            /*
             * close any jdbc instances here that weren't
             * explicitly closed during normal code path, so
             * that we don't 'leak' resources...
             */

            if (stmt != null) {
                try {
                    stmt.close();
                } catch (sqlexception sqlex) {
                    // ignore -- as we can't do anything about it here
                }

                stmt = null;
            }

            if (conn != null) {
                try {
                    conn.close();
                } catch (sqlexception sqlex) {
                    // ignore -- as we can't do anything about it here
                }

                conn = null;
            }
        }
    }
}

As shown in the example above, after obtaining the JNDI InitialContext, and looking up the DataSource, the rest of the code should look familiar to anyone who has done JDBC programming in the past.

The most important thing to remember when using connection pooling is to make sure that no matter what happens in your code (exceptions, flow-of-control, and so forth), connections, and anything created by them (such as statements or result sets) are closed, so that they may be re-used, otherwise they will be stranded, which in the best case means that the MySQL server resources they represent (such as buffers, locks, or sockets) may be tied up for some time, or worst case, may be tied up forever.

What's the Best Size for my Connection Pool?

As with all other configuration rules-of-thumb, the answer is: it depends. Although the optimal size depends on anticipated load and average database transaction time, the optimum connection pool size is smaller than you might expect. If you take Sun's Java Petstore blueprint application for example, a connection pool of 15-20 connections can serve a relatively moderate load (600 concurrent users) using MySQL and Tomcat with response times that are acceptable.

To correctly size a connection pool for your application, you should create load test scripts with tools such as Apache JMeter or The Grinder, and load test your application.

An easy way to determine a starting point is to configure your connection pool's maximum number of connections to be unbounded, run a load test, and measure the largest amount of concurrently used connections. You can then work backward from there to determine what values of minimum and maximum pooled connections give the best performance for your particular application.

27.4.5.2.2. Using Connector/J with Tomcat

The following instructions are based on the instructions for Tomcat-5.x, available at http://tomcat.apache.org/tomcat-5.5-doc/jndi-datasource-examples-howto.html which is current at the time this document was written.

First, install the .jar file that comes with Connector/J in $CATALINA_HOME/common/lib so that it is available to all applications installed in the container.

Next, Configure the JNDI DataSource by adding a declaration resource to $CATALINA_HOME/conf/server.xml in the context that defines your web application:

<Context ....>

  ...

  <Resource name="jdbc/MySQLDB"
               auth="Container"
               type="javax.sql.DataSource"/>

  <!-- The name you used above, must match _exactly_ here!

       The connection pool will be bound into JNDI with the name
       "java:/comp/env/jdbc/MySQLDB"
  -->

  <ResourceParams name="jdbc/MySQLDB">
    <parameter>
      <name>factory</name>
      <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
    </parameter>

    <!-- Don't set this any higher than max_connections on your
         MySQL server, usually this should be a 10 or a few 10's
         of connections, not hundreds or thousands -->

    <parameter>
      <name>maxActive</name>
      <value>10</value>
    </parameter>

    <!-- You don't want to many idle connections hanging around
         if you can avoid it, only enough to soak up a spike in
         the load -->

    <parameter>
      <name>maxIdle</name>
      <value>5</value>
    </parameter>

    <!-- Don't use autoReconnect=true, it's going away eventually
         and it's a crutch for older connection pools that couldn't
         test connections. You need to decide whether your application
         is supposed to deal with SQLExceptions (hint, it should), and
         how much of a performance penalty you're willing to pay
         to ensure 'freshness' of the connection -->

    <parameter>
      <name>validationQuery</name>
      <value>SELECT 1</value>
    </parameter>

   <!-- The most conservative approach is to test connections
        before they're given to your application. For most applications
        this is okay, the query used above is very small and takes
        no real server resources to process, other than the time used
        to traverse the network.

        If you have a high-load application you'll need to rely on
        something else. -->

    <parameter>
      <name>testOnBorrow</name>
      <value>true</value>
    </parameter>

   <!-- Otherwise, or in addition to testOnBorrow, you can test
        while connections are sitting idle -->

    <parameter>
      <name>testWhileIdle</name>
      <value>true</value>
    </parameter>

    <!-- You have to set this value, otherwise even though
         you've asked connections to be tested while idle,
         the idle evicter thread will never run -->

    <parameter>
      <name>timeBetweenEvictionRunsMillis</name>
      <value>10000</value>
    </parameter>

    <!-- Don't allow connections to hang out idle too long,
         never longer than what wait_timeout is set to on the
         server...A few minutes or even fraction of a minute
         is sometimes okay here, it depends on your application
         and how much spikey load it will see -->

    <parameter>
      <name>minEvictableIdleTimeMillis</name>
      <value>60000</value>
    </parameter>

    <!-- Username and password used when connecting to MySQL -->

    <parameter>
     <name>username</name>
     <value>someuser</value>
    </parameter>

    <parameter>
     <name>password</name>
     <value>somepass</value>
    </parameter>

    <!-- Class name for the Connector/J driver -->

    <parameter>
       <name>driverClassName</name>
       <value>com.mysql.jdbc.Driver</value>
    </parameter>

    <!-- The JDBC connection url for connecting to MySQL, notice
         that if you want to pass any other MySQL-specific parameters
         you should pass them here in the URL, setting them using the
         parameter tags above will have no effect, you will also
         need to use &amp; to separate parameter values as the
         ampersand is a reserved character in XML -->

    <parameter>
      <name>url</name>
      <value>jdbc:mysql://localhost:3306/test</value>
    </parameter>

  </ResourceParams>
</Context>

In general, you should follow the installation instructions that come with your version of Tomcat, as the way you configure datasources in Tomcat changes from time-to-time, and unfortunately if you use the wrong syntax in your XML file, you will most likely end up with an exception similar to the following:

Error: java.sql.SQLException: Cannot load JDBC driver class 'null ' SQL
state: null 
27.4.5.2.3. Using Connector/J with JBoss

These instructions cover JBoss-4.x. To make the JDBC driver classes available to the application server, copy the .jar file that comes with Connector/J to the lib directory for your server configuration (which is usually called default). Then, in the same configuration directory, in the subdirectory named deploy, create a datasource configuration file that ends with "-ds.xml", which tells JBoss to deploy this file as a JDBC Datasource. The file should have the following contents:

<datasources>
    <local-tx-datasource>
        <!-- This connection pool will be bound into JNDI with the name
             "java:/MySQLDB" -->

        <jndi-name>MySQLDB</jndi-name>
        <connection-url>jdbc:mysql://localhost:3306/dbname</connection-url>
        <driver-class>com.mysql.jdbc.Driver</driver-class>
        <user-name>user</user-name>
        <password>pass</password>

        <min-pool-size>5</min-pool-size>

        <!-- Don't set this any higher than max_connections on your
         MySQL server, usually this should be a 10 or a few 10's
         of connections, not hundreds or thousands -->

        <max-pool-size>20</max-pool-size>

        <!-- Don't allow connections to hang out idle too long,
         never longer than what wait_timeout is set to on the
         server...A few minutes is usually okay here,
         it depends on your application
         and how much spikey load it will see -->

        <idle-timeout-minutes>5</idle-timeout-minutes>

        <!-- If you're using Connector/J 3.1.8 or newer, you can use
             our implementation of these to increase the robustness
             of the connection pool. -->

        <exception-sorter-class-name> 
  com.mysql.jdbc.integration.jboss.ExtendedMysqlExceptionSorter
        </exception-sorter-class-name>
        <valid-connection-checker-class-name>
  com.mysql.jdbc.integration.jboss.MysqlValidConnectionChecker
        </valid-connection-checker-class-name>

    </local-tx-datasource>
</datasources> 
27.4.5.2.4. Using Connector/J with Spring

The Spring Framework is a Java-based application framework designed for assisting in application design by providing a way to configure components. The technique used by Spring is a well known design pattern called Dependency Injection (see Inversion of Control Containers and the Dependency Injection pattern). This article will focus on Java-oriented access to MySQL databases with Spring 2.0. For those wondering, there is a .NET port of Spring appropriately named Spring.NET.

Spring is not only a system for configuring components, but also includes support for aspect oriented programming (AOP). This is one of the main benefits and the foundation for Spring's resource and transaction management. Spring also provides utilities for integrating resource management with JDBC and Hibernate.

For the examples in this section the MySQL world sample database will be used. The first task is to set up a MySQL data source through Spring. Components within Spring use the "bean" terminology. For example, to configure a connection to a MySQL server supporting the world sample database you might use:

<util:map id="dbProps">
    <entry key="db.driver" value="com.mysql.jdbc.Driver"/>
    <entry key="db.jdbcurl" value="jdbc:mysql://localhost/world"/>
    <entry key="db.username" value="myuser"/>
    <entry key="db.password" value="mypass"/>
</util:map>

        

In the above example we are assigning values to properties that will be used in the configuration. For the datasource configuration:

<bean id="dataSource" 
       class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="${db.driver}"/>
    <property name="url" value="${db.jdbcurl}"/>
    <property name="username" value="${db.username}"/>
    <property name="password" value="${db.password}"/>
</bean>
        

The placeholders are used to provide values for properties of this bean. This means that you can specify all the properties of the configuration in one place instead of entering the values for each property on each bean. We do, however, need one more bean to pull this all together. The last bean is responsible for actually replacing the placeholders with the property values.

<bean 
 class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="properties" ref="dbProps"/>
</bean>
        

Now that we have our MySQL data source configured and ready to go, we write some Java code to access it. The example below will retrieve three random cities and their corresponding country using the data source we configured with Spring.

// Create a new application context. this processes the Spring config
ApplicationContext ctx =
    new ClassPathXmlApplicationContext("ex1appContext.xml");
// Retrieve the data source from the application context
    DataSource ds = (DataSource) ctx.getBean("dataSource");
// Open a database connection using Spring's DataSourceUtils
Connection c = DataSourceUtils.getConnection(ds);
try {
    // retrieve a list of three random cities
    PreparedStatement ps = c.prepareStatement(
        "select City.Name as 'City', Country.Name as 'Country' " +
        "from City inner join Country on City.CountryCode = Country.Code " +
        "order by rand() limit 3");
    ResultSet rs = ps.executeQuery();
    while(rs.next()) {
        String city = rs.getString("City");
        String country = rs.getString("Country");
        System.out.printf("The city %s is in %s%n", city, country);
    }
} catch (SQLException ex) {
    // something has failed and we print a stack trace to analyse the error
    ex.printStackTrace();
    // ignore failure closing connection
    try { c.close(); } catch (SQLException e) { }
} finally {
    // properly release our connection
    DataSourceUtils.releaseConnection(c, ds);
}

This is very similar to normal JDBC access to MySQL with the main difference being that we are using DataSourceUtils instead of the DriverManager to create the connection.

While it may seem like a small difference, the implications are somewhat far reaching. Spring manages this resource in a way similar to a container managed data source in a J2EE application server. When a connection is opened, it can be subsequently accessed in other parts of the code if it is synchronized with a transaction. This makes it possible to treat different parts of your application as transactional instead of passing around a database connection.

27.4.5.2.4.1. Using JdbcTemplate

Spring makes extensive use of the Template method design pattern (see Template Method Pattern). Our immediate focus will be on the JdbcTemplate and related classes, specifically NamedParameterJdbcTemplate. The template classes handle obtaining and releasing a connection for data access when one is needed.

The next example shows how to use NamedParameterJdbcTemplate inside of a DAO (Data Access Object) class to retrieve a random city given a country code.

public class Ex2JdbcDao {
     /**
     * Data source reference which will be provided by Spring.
     */
     private DataSource dataSource;
        
     /**
     * Our query to find a random city given a country code. Notice
     * the ":country" parameter towards the end. This is called a
     * named parameter.
     */
     private String queryString = "select Name from City " +
        "where CountryCode = :country order by rand() limit 1";
        
     /**
     * Retrieve a random city using Spring JDBC access classes.
     */
     public String getRandomCityByCountryCode(String cntryCode) {
         // A template that allows using queries with named parameters
         NamedParameterJdbcTemplate template =
         new NamedParameterJdbcTemplate(dataSource);
         // A java.util.Map is used to provide values for the parameters
         Map params = new HashMap();
         params.put("country", cntryCode);
         // We query for an Object and specify what class we are expecting
         return (String)template.queryForObject(queryString, params, String.class);
     }
        
    /**
    * A JavaBean setter-style method to allow Spring to inject the data source.
    * @param dataSource
    */
    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }
}
   

The focus in the above code is on the getRandomCityByCountryCode() method. We pass a country code and use the NamedParameterJdbcTemplate to query for a city. The country code is placed in a Map with the key "country", which is the parameter is named in the SQL query.

To access this code, you need to configure it with Spring by providing a reference to the data source.

<bean id="dao" class="code.Ex2JdbcDao">
    <property name="dataSource" ref="dataSource"/>
</bean>

At this point, we can just grab a reference to the DAO from Spring and call getRandomCityByCountryCode().

// Create the application context
    ApplicationContext ctx =
    new ClassPathXmlApplicationContext("ex2appContext.xml");
    // Obtain a reference to our DAO
    Ex2JdbcDao dao = (Ex2JdbcDao) ctx.getBean("dao");
        
    String countryCode = "USA";
        
    // Find a few random cities in the US
    for(int i = 0; i < 4; ++i)
        System.out.printf("A random city in %s is %s%n", countryCode,
            dao.getRandomCityByCountryCode(countryCode));

This example shows how to use Spring's JDBC classes to completely abstract away the use of traditional JDBC classes including Connection and PreparedStatement.

27.4.5.2.4.2. Transactional JDBC Access

You might be wondering how we can add transactions into our code if we don't deal directly with the JDBC classes. Spring provides a transaction management package that not only replaces JDBC transaction management, but also allows declarative transaction management (configuration instead of code).

In order to use transactional database access, we will need to change the storage engine of the tables in the world database. The downloaded script explicitly creates MyISAM tables which do not support transactional semantics. The InnoDB storage engine does support transactions and this is what we will be using. We can change the storage engine with the following statements.

ALTER TABLE City ENGINE=InnoDB;
ALTER TABLE Country ENGINE=InnoDB;
ALTER TABLE CountryLanguage ENGINE=InnoDB;

A good programming practice emphasized by Spring is separating interfaces and implementations. What this means is that we can create a Java interface and only use the operations on this interface without any internal knowledge of what the actual implementation is. We will let Spring manage the implementation and with this it will manage the transactions for our implementation.

First you create a simple interface:

public interface Ex3Dao {
    Integer createCity(String name, String countryCode,
    String district, Integer population);
}

This interface contains one method that will create a new city record in the database and return the id of the new record. Next you need to create an implementation of this interface.

public class Ex3DaoImpl implements Ex3Dao {
    protected DataSource dataSource;
    protected SqlUpdate updateQuery;
    protected SqlFunction idQuery;
        
    public Integer createCity(String name, String countryCode,
        String district, Integer population) {
            updateQuery.update(new Object[] { name, countryCode,
                   district, population });
            return getLastId();
        }
        
    protected Integer getLastId() {
        return idQuery.run();
    }
}

You can see that we only operate on abstract query objects here and don't deal directly with the JDBC API. Also, this is the complete implementation. All of our transaction management will be dealt with in the configuration. To get the configuration started, we need to create the DAO.

<bean id="dao" class="code.Ex3DaoImpl">
    <property name="dataSource" ref="dataSource"/>
    <property name="updateQuery">...</property>
    <property name="idQuery">...</property>
</bean>

Now you need to set up the transaction configuration. The first thing you must do is create transaction manager to manage the data source and a specification of what transaction properties are required for for the dao methods.

<bean id="transactionManager" 
  class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource" ref="dataSource"/>
</bean>
        
<tx:advice id="txAdvice" transaction-manager="transactionManager">
    <tx:attributes>
        <tx:method name="*"/>
    </tx:attributes>
</tx:advice>

The preceding code creates a transaction manager that handles transactions for the data source provided to it. The txAdvice uses this transaction manager and the attributes specify to create a transaction for all methods. Finally you need to apply this advice with an AOP pointcut.

<aop:config>
    <aop:pointcut id="daoMethods"
        expression="execution(* code.Ex3Dao.*(..))"/>
     <aop:advisor advice-ref="txAdvice" pointcut-ref="daoMethods"/>
</aop:config>

This basically says that all methods called on the Ex3Dao interface will be wrapped in a transaction. To make use of this, you only have to retrieve the dao from the application context and call a method on the dao instance.

Ex3Dao dao = (Ex3Dao) ctx.getBean("dao");
Integer id = dao.createCity(name,  countryCode, district, pop);

We can verify from this that there is no transaction management happening in our Java code and it's all configured with Spring. This is a very powerful notion and regarded as one of the most beneficial features of Spring.

27.4.5.2.4.3. Connection Pooling

In many sitations, such as web applications, there will be a large number of small database transactions. When this is the case, it usually makes sense to create a pool of database connections available for web requests as needed. Although MySQL does not spawn an extra process when a connection is made, there is still a small amount of overhead to create and set up the connection. Pooling of connections also alleviates problems such as collecting large amounts of sockets in the TIME_WAIT state.

Setting up pooling of MySQL connections with Spring is as simple as changing the data source configuration in the application context. There are a number of configurations that we can use. The first example is based on the Jakarta Commons DBCP library. The example below replaces the source configuration that was based on DriverManagerDataSource with DBCP's BasicDataSource.

<bean id="dataSource" destroy-method="close"
  class="org.apache.commons.dbcp.BasicDataSource">
    <property name="driverClassName" value="${db.driver}"/>
    <property name="url" value="${db.jdbcurl}"/>
    <property name="username" value="${db.username}"/>
    <property name="password" value="${db.password}"/>
    <property name="initialSize" value="3"/>
</bean>

The configuration of the two solutions is very similar. The difference is that DBCP will pool connections to the database instead of creating a new connection every time one is requested. We have also set a parameter here called initialSize. This tells DBCP that we want three connections in the pool when it is created.

Another way to configure connection pooling is to configure a data source in our J2EE application server. Using JBoss as an example, you can set up the MySQL connection pool by creating a file called mysql-local-ds.xml and placing it in the server/default/deploy directory in JBoss. Once we have this setup, we can use JNDI to look it up. With Spring, this lookup is very simple. The data source configuration looks like this.

<jee:jndi-lookup id="dataSource" jndi-name="java:MySQL_DS"/>
27.4.5.2.5. Using Connector/J with GlassFish

27.4.5.3. Common Problems and Solutions

There are a few issues that seem to be commonly encountered often by users of MySQL Connector/J. This section deals with their symptoms, and their resolutions.

Questions

  • 28.4.5.3.1: When I try to connect to the database with MySQL Connector/J, I get the following exception:

    SQLException: Server configuration denies access to data source
    SQLState: 08001
    VendorError: 0

    What's going on? I can connect just fine with the MySQL command-line client.

  • 28.4.5.3.2: My application throws an SQLException 'No Suitable Driver'. Why is this happening?

  • 28.4.5.3.3: I'm trying to use MySQL Connector/J in an applet or application and I get an exception similar to:

    SQLException: Cannot connect to MySQL server on host:3306.
    Is there a MySQL server running on the machine/port you
    are trying to connect to?
    
    (java.security.AccessControlException)
    SQLState: 08S01
    VendorError: 0 
  • 28.4.5.3.4: I have a servlet/application that works fine for a day, and then stops working overnight

  • 28.4.5.3.5: I'm trying to use JDBC-2.0 updatable result sets, and I get an exception saying my result set is not updatable.

  • 28.4.5.3.6: I cannot connect to the MySQL server using Connector/J, and I'm sure the connection paramters are correct.

  • 28.4.5.3.7: I am trying to connect to my MySQL server within my application, but I get the following error and stack trace:

    java.net.SocketException
    MESSAGE: Software caused connection abort: recv failed
    
    STACKTRACE:
    
    java.net.SocketException: Software caused connection abort: recv failed
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.read(Unknown Source)
    at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1392)
    at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:1414)
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:625)
    at com.mysql.jdbc.Connection.createNewIO(Connection.java:1926)
    at com.mysql.jdbc.Connection.<init>(Connection.java:452)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:411)
  • 28.4.5.3.8: My application is deployed through JBoss and I am using transactions to handle the statements on the MySQL database. Under heavy loads I am getting a error and stack trace, but these only occur after a fixed period of heavy activity.

  • 28.4.5.3.9: When using gcj an java.io.CharConversionException is raised when working with certain character sequences.

  • 28.4.5.3.10: Updating a table that contains a primary key that is either FLOAT or compound primary key that uses FLOAT fails to update the table and raises an exception.

Questions and Answers

28.4.5.3.1: When I try to connect to the database with MySQL Connector/J, I get the following exception:

SQLException: Server configuration denies access to data source
SQLState: 08001
VendorError: 0

What's going on? I can connect just fine with the MySQL command-line client.

MySQL Connector/J must use TCP/IP sockets to connect to MySQL, as Java does not support Unix Domain Sockets. Therefore, when MySQL Connector/J connects to MySQL, the security manager in MySQL server will use its grant tables to determine whether the connection should be allowed.

You must add the necessary security credentials to the MySQL server for this to happen, using the GRANT statement to your MySQL Server. See Section 12.5.1.3, “GRANT Syntax”, for more information.

Note

Testing your connectivity with the mysql command-line client will not work unless you add the --host flag, and use something other than localhost for the host. The mysql command-line client will use Unix domain sockets if you use the special hostname localhost. If you are testing connectivity to localhost, use 127.0.0.1 as the hostname instead.

Warning

Changing privileges and permissions improperly in MySQL can potentially cause your server installation to not have optimal security properties.

28.4.5.3.2: My application throws an SQLException 'No Suitable Driver'. Why is this happening?

There are three possible causes for this error:

  • The Connector/J driver is not in your CLASSPATH, see Section 27.4.2, “Connector/J Installation”.

  • The format of your connection URL is incorrect, or you are referencing the wrong JDBC driver.

  • When using DriverManager, the jdbc.drivers system property has not been populated with the location of the Connector/J driver.

28.4.5.3.3: I'm trying to use MySQL Connector/J in an applet or application and I get an exception similar to:

SQLException: Cannot connect to MySQL server on host:3306.
Is there a MySQL server running on the machine/port you
are trying to connect to?

(java.security.AccessControlException)
SQLState: 08S01
VendorError: 0 

Either you're running an Applet, your MySQL server has been installed with the "--skip-networking" option set, or your MySQL server has a firewall sitting in front of it.

Applets can only make network connections back to the machine that runs the web server that served the .class files for the applet. This means that MySQL must run on the same machine (or you must have some sort of port re-direction) for this to work. This also means that you will not be able to test applets from your local file system, you must always deploy them to a web server.

MySQL Connector/J can only communicate with MySQL using TCP/IP, as Java does not support Unix domain sockets. TCP/IP communication with MySQL might be affected if MySQL was started with the "--skip-networking" flag, or if it is firewalled.

If MySQL has been started with the "--skip-networking" option set (the Debian Linux package of MySQL server does this for example), you need to comment it out in the file /etc/mysql/my.cnf or /etc/my.cnf. Of course your my.cnf file might also exist in the data directory of your MySQL server, or anywhere else (depending on how MySQL was compiled for your system). Binaries created by MySQL AB always look in /etc/my.cnf and [datadir]/my.cnf. If your MySQL server has been firewalled, you will need to have the firewall configured to allow TCP/IP connections from the host where your Java code is running to the MySQL server on the port that MySQL is listening to (by default, 3306).

28.4.5.3.4: I have a servlet/application that works fine for a day, and then stops working overnight

MySQL closes connections after 8 hours of inactivity. You either need to use a connection pool that handles stale connections or use the "autoReconnect" parameter (see Section 27.4.4.1, “Driver/Datasource Class Names, URL Syntax and Configuration Properties for Connector/J”).

Also, you should be catching SQLExceptions in your application and dealing with them, rather than propagating them all the way until your application exits, this is just good programming practice. MySQL Connector/J will set the SQLState (see java.sql.SQLException.getSQLState() in your APIDOCS) to "08S01" when it encounters network-connectivity issues during the processing of a query. Your application code should then attempt to re-connect to MySQL at this point.

The following (simplistic) example shows what code that can handle these exceptions might look like:

Example 27.12. Example of transaction with retry logic

public void doBusinessOp() throws SQLException {
    Connection conn = null;
    Statement stmt = null;
    ResultSet rs = null;

    //
    // How many times do you want to retry the transaction
    // (or at least _getting_ a connection)?
    //
    int retryCount = 5;

    boolean transactionCompleted = false;

    do {
        try {
            conn = getConnection(); // assume getting this from a
                                    // javax.sql.DataSource, or the
                                    // java.sql.DriverManager

            conn.setAutoCommit(false);

            //
            // Okay, at this point, the 'retry-ability' of the
            // transaction really depends on your application logic,
            // whether or not you're using autocommit (in this case
            // not), and whether you're using transacational storage
            // engines
            //
            // For this example, we'll assume that it's _not_ safe
            // to retry the entire transaction, so we set retry
            // count to 0 at this point
            //
            // If you were using exclusively transaction-safe tables,
            // or your application could recover from a connection going
            // bad in the middle of an operation, then you would not
            // touch 'retryCount' here, and just let the loop repeat
            // until retryCount == 0.
            //
            retryCount = 0;

            stmt = conn.createStatement();

            String query = "SELECT foo FROM bar ORDER BY baz";

            rs = stmt.executeQuery(query);

            while (rs.next()) {
            }

            rs.close();
            rs = null;

            stmt.close();
            stmt = null;

            conn.commit();
            conn.close();
            conn = null;

            transactionCompleted = true;
        } catch (SQLException sqlEx) {

            //
            // The two SQL states that are 'retry-able' are 08S01
            // for a communications error, and 40001 for deadlock.
            //
            // Only retry if the error was due to a stale connection,
            // communications problem or deadlock
            //

            String sqlState = sqlEx.getSQLState();

            if ("08S01".equals(sqlState) || "40001".equals(sqlState)) {
                retryCount--;
            } else {
                retryCount = 0;
            }
        } finally {
            if (rs != null) {
                try {
                    rs.close();
                } catch (SQLException sqlEx) {
                    // You'd probably want to log this . . .
                }
            }

            if (stmt != null) {
                try {
                    stmt.close();
                } catch (SQLException sqlEx) {
                    // You'd probably want to log this as well . . .
                }
            }

            if (conn != null) {
                try {
                    //
                    // If we got here, and conn is not null, the
                    // transaction should be rolled back, as not
                    // all work has been done

                    try {
                        conn.rollback();
                    } finally {
                        conn.close();
                    }
                } catch (SQLException sqlEx) {
                    //
                    // If we got an exception here, something
                    // pretty serious is going on, so we better
                    // pass it up the stack, rather than just
                    // logging it. . .

                    throw sqlEx;
                }
            }
        }
    } while (!transactionCompleted && (retryCount > 0));
}

Note

Use of the autoReconnect option is not recommended because there is no safe method of reconnecting to the MySQL server without risking some corruption of the connection state or database state information. Instead, you should use a connection pool which will enable your application to connect to the MySQL server using an available connection from the pool. The autoReconnect facility is deprecated, and may be removed in a future release.

28.4.5.3.5: I'm trying to use JDBC-2.0 updatable result sets, and I get an exception saying my result set is not updatable.

Because MySQL does not have row identifiers, MySQL Connector/J can only update result sets that have come from queries on tables that have at least one primary key, the query must select every primary key and the query can only span one table (that is, no joins). This is outlined in the JDBC specification.

Note that this issue only occurs when using updatable result sets, and is caused because Connector/J is unable to guarantee that it can identify the correct rows within the result set to be updated without having a unique reference to each row. There is no requirement to have a unique field on a table if you are using UPDATE or DELETE statements on a table where you can individually specify the criteria to be matched using a WHERE clause.

28.4.5.3.6: I cannot connect to the MySQL server using Connector/J, and I'm sure the connection paramters are correct.

Make sure that the skip-networking option has not been enabled on your server. Connector/J must be able to communicate with your server over TCP/IP, named sockets are not supported. Also ensure that you are not filtering connections through a Firewall or other network security system. For more informaiton, see Section B.1.2.2, “Can't connect to [local] MySQL server.

28.4.5.3.7: I am trying to connect to my MySQL server within my application, but I get the following error and stack trace:

java.net.SocketException
MESSAGE: Software caused connection abort: recv failed

STACKTRACE:

java.net.SocketException: Software caused connection abort: recv failed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(Unknown Source)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1392)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:1414)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:625)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:1926)
at com.mysql.jdbc.Connection.<init>(Connection.java:452)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:411)

The error probably indicates that you are using a older version of the Connector/J JDBC driver (2.0.14 or 3.0.x) and you are trying to connect to a MySQL server with version 4.1x or newer. The older drivers are not compatible with 4.1 or newer of MySQL as they do not support the newer authentication mechanisms.

It is likely that the older version of the Connector/J driver exists within your application directory or your CLASSPATH includes the older Connector/J package.

28.4.5.3.8: My application is deployed through JBoss and I am using transactions to handle the statements on the MySQL database. Under heavy loads I am getting a error and stack trace, but these only occur after a fixed period of heavy activity.

This is a JBoss, not Connector/J, issue and is connected to the use of transactions. Under heavy loads the time taken for transactions to complete can increase, and the error is caused because you have exceeded the predefined timeout.

You can increase the timeout value by setting the TransactionTimeout attribute to the TransactionManagerService within the /conf/jboss-service.xml file (pre-4.0.3) or /deploy/jta-service.xml for JBoss 4.0.3 or later. See TransactionTimeoute within the JBoss wiki for more information.

28.4.5.3.9: When using gcj an java.io.CharConversionException is raised when working with certain character sequences.

This is a known issue with gcj which raises an exception when it reaches an unknown character or one it cannot convert. You should add useJvmCharsetConverters=true to your connection string to force character conversion outside of the gcj libraries, or try a different JDK.

28.4.5.3.10: Updating a table that contains a primary key that is either FLOAT or compound primary key that uses FLOAT fails to update the table and raises an exception.

Connector/J adds conditions to the WHERE clause during an UPDATE to check the old values of the primary key. If there is no match then Connector/J considers this a failure condition and raises an exception.

The problem is that rounding differences between supplied values and the values stored in the database may mean that the values never match, and hence the update fails. The issue will affect all queries, not just those from Connector/J.

To prevent this issue, use a primary key that does not use FLOAT. If you have to use a floating point column in your primary key use DOUBLE or DECIMAL types in place of FLOAT.

27.4.6. Connector/J Support

27.4.6.1. Connector/J Community Support

MySQL AB provides assistance to the user community by means of its mailing lists. For Connector/J related issues, you can get help from experienced users by using the MySQL and Java mailing list. Archives and subscription information is available online at http://lists.mysql.com/java.

For information about subscribing to MySQL mailing lists or to browse list archives, visit http://lists.mysql.com/. See Section 1.6.1, “MySQL Mailing Lists”.

Community support from experienced users is also available through the JDBC Forum. You may also find help from other users in the other MySQL Forums, located at http://forums.mysql.com. See Section 1.6.2, “MySQL Community Support at the MySQL Forums”.

27.4.6.2. How to Report Connector/J Bugs or Problems

The normal place to report bugs is http://bugs.mysql.com/, which is the address for our bugs database. This database is public, and can be browsed and searched by anyone. If you log in to the system, you will also be able to enter new reports.

If you have found a sensitive security bug in MySQL, you can send email to .

Writing a good bug report takes patience, but doing it right the first time saves time both for us and for yourself. A good bug report, containing a full test case for the bug, makes it very likely that we will fix the bug in the next release.

This section will help you write your report correctly so that you don't waste your time doing things that may not help us much or at all.

If you have a repeatable bug report, please report it to the bugs database at http://bugs.mysql.com/. Any bug that we are able to repeat has a high chance of being fixed in the next MySQL release.

To report other problems, you can use one of the MySQL mailing lists.

Remember that it is possible for us to respond to a message containing too much information, but not to one containing too little. People often omit facts because they think they know the cause of a problem and assume that some details don't matter.

A good principle is this: If you are in doubt about stating something, state it. It is faster and less troublesome to write a couple more lines in your report than to wait longer for the answer if we must ask you to provide information that was missing from the initial report.

The most common errors made in bug reports are (a) not including the version number of Connector/J or MySQL used, and (b) not fully describing the platform on which Connector/J is installed (including the JVM version, and the platform type and version number that MySQL itself is installed on).

This is highly relevant information, and in 99 cases out of 100, the bug report is useless without it. Very often we get questions like, “Why doesn't this work for me?” Then we find that the feature requested wasn't implemented in that MySQL version, or that a bug described in a report has already been fixed in newer MySQL versions.

Sometimes the error is platform-dependent; in such cases, it is next to impossible for us to fix anything without knowing the operating system and the version number of the platform.

If at all possible, you should create a repeatable, stanalone testcase that doesn't involve any third-party classes.

To streamline this process, we ship a base class for testcases with Connector/J, named 'com.mysql.jdbc.util.BaseBugReport'. To create a testcase for Connector/J using this class, create your own class that inherits from com.mysql.jdbc.util.BaseBugReport and override the methods setUp(), tearDown() and runTest().

In the setUp() method, create code that creates your tables, and populates them with any data needed to demonstrate the bug.

In the runTest() method, create code that demonstrates the bug using the tables and data you created in the setUp method.

In the tearDown() method, drop any tables you created in the setUp() method.

In any of the above three methods, you should use one of the variants of the getConnection() method to create a JDBC connection to MySQL:

  • getConnection() - Provides a connection to the JDBC URL specified in getUrl(). If a connection already exists, that connection is returned, otherwise a new connection is created.

  • getNewConnection() - Use this if you need to get a new connection for your bug report (i.e. there's more than one connection involved).

  • getConnection(String url) - Returns a connection using the given URL.

  • getConnection(String url, Properties props) - Returns a connection using the given URL and properties.

If you need to use a JDBC URL that is different from 'jdbc:mysql:///test', override the method getUrl() as well.

Use the assertTrue(boolean expression) and assertTrue(String failureMessage, boolean expression) methods to create conditions that must be met in your testcase demonstrating the behavior you are expecting (vs. the behavior you are observing, which is why you are most likely filing a bug report).

Finally, create a main() method that creates a new instance of your testcase, and calls the run method:

public static void main(String[] args) throws Exception {
      new MyBugReport().run();
 }

Once you have finished your testcase, and have verified that it demonstrates the bug you are reporting, upload it with your bug report to http://bugs.mysql.com/.

27.4.6.3. Connector/J Change History

The Connector/J Change History (Changelog) is located with the main Changelog for MySQL. See Section E.6, “MySQL Connector/J Change History”.

27.5. MySQL Connector/MXJ

MySQL Connector/MXJ is a Java Utility package for deploying and managing a MySQL database. Deploying and using MySQL can be as easy as adding an additional parameter to the JDBC connection url, which will result in the database being started when the first connection is made. This makes it easy for Java developers to deploy applications which require a database by reducing installation barriers for their end-users.

MySQL Connector/MXJ makes the MySQL database appear to be a java-based component. It does this by determining what platform the system is running on, selecting the appropriate binary, and launching the executable. It will also optionally deploy an initial database, with any specified parameters.

Included are instructions for use with a JDBC driver and deploying as a JMX MBean to JBoss.

You can download sources and binaries from: http://dev.mysql.com/downloads/connector/mxj/

This a beta release and feedback is welcome and encouraged.

Please send questions or comments to the MySQL and Java mailing list.

27.5.1. Connector/MXJ Overview

Connector/MXJ consists of a Java class, a copy of the mysqld binary for a specific list of platforms, and associated files and support utilities. The Java class controls the initialization of an instance of the embedded mysqld binary, and the ongoing management of the mysqld process. The entire sequence and management can be controlled entirely from within Java using the Connector/MXJ Java classes. You can see an overview of the contents of the Connector/MXJ package in the figure below.

Connector/MXJ Overview

It is important to note that Connector/MXJ is not an embedded version of MySQL, or a version of MySQL written as part of a Java class. Connector/MXJ works through the use of an embedded, compiled binary of mysqld as would normally be used when deploying a standard MySQL installation.

It is the Connector/MXJ wrapper, support classes and tools, that enable Connector/MXJ to appear as a MySQL instance.

When Connector/MXJ is initialized, the corresponding mysqld binary for the current platform is extracted, along with a pre-configured data directed. Both are contained within the Connector/MXJ JAR file. The mysqld instance is then started, with any additional options as specified during the initialization, and the MySQL database becomes accessible.

Because Connector/MXJ works in combination with Connector/J, you can access and integrate with the MySQL instance through a JDBC connection. When you have finished with the server, the instance is terminated, and, by default, any data created during the session is retained within the temporary directory created when the instance was started.

Connector/MXJ and the embedded mysqld instance can be deployed in a number of environments where relying on an existing database, or installing a MySQL instance would be impossible, including CD-ROM embedded database applications and temporary database requirements within a Java-based application environment.

27.5.2. Connector/MXJ Versions

  • Connector/MXJ 5.x, currently in beta status, includes mysqld version 5.x and includes binaries for Linux x86, Mac OS X PPC, Windows XP/NT/2000 x86 and Solaris SPARC. Connector/MXJ 5.x requires the Connector/J 5.x package.

    The exact version of mysqld included depends on the version of Connector/MXJ

    1. Connector/MXJ v5.0.3 included MySQL v5.0.22

    2. Connector/MXJ v5.0.4 includes MySQL v5.0.27 (Community) or MySQL v5.0.32 (Enterprise)

    3. Connector/MXJ v5.0.6 includes MySQL 5.0.37 (Community)

    4. Connector/MXJ v5.0.7 includes MySQL 5.0.41 (Community) or MySQL 5.0.42 (Enterprise)

    5. Connector/MXJ v5.0.8 includes MySQL 5.0.45 (Community) or MySQL 5.0.46 (Enterprise)

    6. Connector/MXJ v5.0.9 includes MySQL 5.0.51a (Community) or MySQL 5.0.54 (Enterprise)

  • Connector/MXJ 1.x includes mysqld version 4.1.13 and includes binaries for Linux x86, Windows XP/NT/2000 x86 and Solaris SPARC. Connector/MXJ 1.x requires the Connector/J 3.x package.

A summary of the different MySQL versions supplied with each Connector/MXJ release are shown in the table.

Connector/MXJ VersionMySQL Version(s)
5.0.85.0.45 (CS), 5.0.46 (ES)
5.0.75.0.41 (CS), 5.0.42 (ES)
5.0.65.0.37 (CS), 5.0.40 (ES)
5.0.55.0.37 (CS), 5.0.36 (ES)
5.0.45.0.27 (CS), 5.0.32 (ES)
5.0.35.0.22
5.0.25.0.19

This guide provides information on the Connector/MXJ 5.x release. For information on using the older releases, please see the documentation included with the appropriate distribution.

27.5.3. Connector/MXJ Installation

Connector/MXJ does not have a installation application or process, but there are some steps you can follow to make the installation and deployment of Connector/MXJ easier.

Before you start, there are some baseline requirements for

  • Java Runtime Environment (v1.4.0 or newer) if you are only going to deploy the package.

  • Java Development Kit (v1.4.0 or newer) if you want to build Connector/MXJ from source.

  • Connector/J 5.0 or newer.

Depending on your target installation/deployment environment you may also require:

27.5.3.1. Supported Platforms

Connector/MXJ is compatible with any platform supporting Java and MySQL. By default, Connector/MXJ incorporates the mysqld binary for a select number of platforms which differs by version. The following platforms have been tested and working as deployment platforms. Support for all the platforms listed below is not included by default.

  • Linux (i386)

  • FreeBSD (i386)

  • Windows NT (x86), Windows 2000 (x86), Windows XP (x86), Windows Vista (x86)

  • Solaris 8, SPARC 32-bit (compatible with Solaris 8, Solaris 9 and Solaris 10 on SPARC 32-bit and 64-bit platforms)

  • Mac OS X (PowerPC and Intel)

The Connector/MXJ 5.0.8 release includes mysqld binaries for the following platforms by as standard:

  • Linux (i386)

  • Windows (x86), compatible with Windows NT, Windows 2000, Windows XP , Windows Vista

  • Solaris 8, SPARC 32-bit (compatible with Solaris 8, Solaris 9 and Solaris 10 on SPARC 32-bit and 64-bit platforms)

  • Mac OS X (PowerPC and Intel)

For more information on packaging your own Connector/MXJ with the platforms you require, see Section 27.5.6.1, “Creating your own Connector/MXJ Package”

27.5.3.2. Connector/MXJ Base Installation

Because there is no formal installation process, the method, installation directory, and access methods you use for Connector/MXJ are entirely up to your individual requirements.

To perform a basic installation, choose a target directory for the files included in the Connector/MXJ package. On Unix/Linux systems you may opt to use a directory such as /usr/local/connector-mxj; On Windows, you may want to install the files in the base directory, C:\Connector-MXJ, or within the Program Files directory.

To install the files, for a Connector/MXJ 5.0.4 installation:

  1. Download the Connector/MXJ package, either in Tar/Gzip format (ideal for Unix/Linux systems) or Zip format (Windows).

  2. Extract the files from the package. This will create a directory mysql-connector-mxj-gpl-[ver]. Copy and optionally rename this directory to your desired location.

  3. For best results, you should update your global CLASSPATH variable with the location of the required jar files.

    Within Unix/Linux you can do this globally by editing the global shell profile, or on a user by user basis by editing their individual shell profile.

    On Windows 2000, Windows NT and Windows XP, you can edit the global CLASSPATH by editing the Environment Variables configured through the System control panel.

For Connector/MXJ 5.0.6 and later you need the following JAR files in your CLASSPATH:

  1. mysql-connector-mxj-gpl-[ver].jar — contains the main Connector/MXJ classes.

  2. mysql-connector-mxj-gpl-[ver]-db-files.jar — contains the embedded mysqld and database files.

  3. aspectjrt.jar — the AspectJ runtime library, located in lib/aspectjrt.jar in the Connector/MXJ package.

  4. mysql-connector-java-[ver]-bin.jar — Connector/J, see Section 27.4, “MySQL Connector/J”.

For Connector/MXJ 5.0.4 and later you need the following JAR files in your CLASSPATH:

  1. connector-mxj.jar — contains the main Connector/MXJ classes.

  2. connector-mxj-db-files.jar — contains the embedded mysqld and database files.

  3. aspectjrt.jar — the AspectJ runtime library, located in lib/aspectjrt.jar in the Connector/MXJ package.

  4. mysql-connector-mxj-gpl-[ver].jar — Connector/J, see Section 27.4, “MySQL Connector/J”.

For Connector/MXJ 5.0.3 and earlier, you need the following JAR files:

  1. connector-mxj.jar

  2. aspectjrt.jar — the AspectJ runtime library, located in lib/aspectjrt.jar in the Connector/MXJ package.

  3. mysql-connector-mxj-gpl-[ver].jar — Connector/J, see Section 27.4, “MySQL Connector/J”.

27.5.3.3. Connector/MXJ Quick Start Guide

Once you have extracted the Connector/MXJ and Connector/J components you can run one of the sample applications that initiates a MySQL instance. You can test the installation by running the ConnectorMXJUrlTestExample:

$ java ConnectorMXJUrlTestExample
jdbc:mysql:mxj://localhost:3336/our_test_app?server.basedir»
    =/var/tmp/test-mxj&createDatabaseIfNotExist=true&server.initialize-user=true
[/var/tmp/test-mxj/bin/mysqld][--no-defaults][--port=3336][--socket=mysql.sock]»
    [--basedir=/var/tmp/test-mxj][--datadir=/var/tmp/test-mxj/data]»
    [--pid-file=/var/tmp/test-mxj/data/MysqldResource.pid]
[MysqldResource] launching mysqld (driver_launched_mysqld_1)
InnoDB: The first specified data file ./ibdata1 did not exist:
InnoDB: a new database to be created!
080220  9:40:20  InnoDB: Setting file ./ibdata1 size to 10 MB
InnoDB: Database physically writes the file full: wait...
080220  9:40:20  InnoDB: Log file ./ib_logfile0 did not exist: new to be created
InnoDB: Setting log file ./ib_logfile0 size to 5 MB
InnoDB: Database physically writes the file full: wait...
080220  9:40:20  InnoDB: Log file ./ib_logfile1 did not exist: new to be created
InnoDB: Setting log file ./ib_logfile1 size to 5 MB
InnoDB: Database physically writes the file full: wait...
InnoDB: Doublewrite buffer not found: creating new
InnoDB: Doublewrite buffer created
InnoDB: Creating foreign key constraint system tables
InnoDB: Foreign key constraint system tables created
080220  9:40:21  InnoDB: Started; log sequence number 0 0
080220  9:40:21 [Note] /var/tmp/test-mxj/bin/mysqld: ready for connections.
Version: '5.0.51a'  socket: 'mysql.sock'  port: 3336  MySQL Community Server (GPL)
[MysqldResource] mysqld running as process: 2238
------------------------
SELECT VERSION()
------------------------
5.0.51a
------------------------
[MysqldResource] stopping mysqld (process: 2238)
080220  9:40:27 [Note] /var/tmp/test-mxj/bin/mysqld: Normal shutdown

080220  9:40:27  InnoDB: Starting shutdown...
080220  9:40:29  InnoDB: Shutdown completed; log sequence number 0 43655
080220  9:40:29 [Note] /var/tmp/test-mxj/bin/mysqld: Shutdown complete

[MysqldResource] shutdown complete

The above output shows an instance of MySQL starting, the necessary files being created (log files, InnoDB data files) and the MySQL database entering the running state. The instance is then shutdown by Connector/MXJ before the example terminates.

27.5.3.4. Deploying Connector/MXJ using Driver Launch

Connector/MXJ and Connector/J work together to enable you to launch an instance of the mysqld server through the use of a keyword in the JDBC connection string. Deploying Connector/MXJ within a Java application can be automated through this method, making the deployment of Connector/MXJ a simple process:

  1. Download and unzip Connector/MXJ, add mysql-connector-mxj-gpl-[ver].jar to the CLASSPATH.

    If you are using Connector/MXJ v5.0.4 or later you will also need to add the mysql-connector-mxj-gpl-[ver]-db-files.jar file to your CLASSPATH.

  2. To the JDBC connection string, embed the mxj keyword, for example: jdbc:mysql:mxj://localhost:PORT/DBNAME.

For more details, see Section 27.5.4, “Connector/MXJ Configuration”.

27.5.3.5. Deploying Connector/MXJ within JBoss

For deployment within a JBoss environment, you must configure the JBoss environment to use the Connector/MXJ component within the JDBC parameters:

  1. Download Connector/MXJ and copy the mysql-connector-mxj-gpl-[ver].jar file to the $JBOSS_HOME/server/default/lib directory.

    If you are using Connector/MXJ v5.0.4 or later you will also need to copy the mysql-connector-mxj-gpl-[ver]-db-files.jar file to $JBOSS_HOME/server/default/lib.

  2. Download Connector/J and copy the mysql-connector-java-5.1.5-bin.jar file to the $JBOSS_HOME/server/default/lib directory.

  3. Create an MBean service xml file in the $JBOSS_HOME/server/default/deploy directory with any attributes set, for instance the datadir and autostart.

  4. Set the JDBC parameters of your web application to use:

    String driver = "com.mysql.jdbc.Driver"; 
    String url = "jdbc:mysql:///test?propertiesTransform="+
                 "com.mysql.management.jmx.ConnectorMXJPropertiesTransform"; 
    String user = "root"; 
    String password = ""; 
    Class.forName(driver);
    Connection conn = DriverManager.getConnection(url, user, password); 

You may wish to create a separate users and database table spaces for each application, rather than using "root and test".

We highly suggest having a routine backup procedure for backing up the database files in the datadir.

27.5.3.6. Verifying Installation using JUnit

The best way to ensure that your platform is supported is to run the JUnit tests. These will test the Connector/MXJ classes and the associated components.

27.5.3.6.1. JUnit Test Requirements

The first thing to do is make sure that the components will work on the platform. The MysqldResource class is really a wrapper for a native version of MySQL, so not all platforms are supported. At the time of this writing, Linux on the i386 architecture has been tested and seems to work quite well, as does OS X v10.3. There has been limited testing on Windows and Solaris.

Requirements:

  1. JDK-1.4 or newer (or the JRE if you aren't going to be compiling the source or JSPs).

  2. MySQL Connector/J version 5.0 or newer (from http://dev.mysql.com/downloads/connector/j/) installed and available via your CLASSPATH.

  3. The javax.management classes for JMX version 1.2.1, these are present in the following application servers:

  4. JUnit 3.8.1 (from http://www.junit.org/).

If building from source, All of the requirements from above, plus:

  1. Ant version 1.5 or newer (download from http://ant.apache.org/).

27.5.3.6.2. Running the JUnit Tests
  1. The tests attempt to launch MySQL on the port 3336. If you have a MySQL running, it may conflict, but this isn't very likely because the default port for MySQL is 3306. However, You may set the "c-mxj_test_port" Java property to a port of your choosing. Alternatively, you may wish to start by shutting down any instances of MySQL you have running on the target machine.

    The tests suppress output to the console by default. For verbose output, you may set the "c-mxj_test_silent" Java property to "false".

  2. To run the JUnit test suite, the $CLASSPATH must include the following:

    • JUnit

    • JMX

    • Connector/J

    • MySQL Connector/MXJ

  3. If connector-mxj.jar is not present in your download, unzip MySQL Connector/MXJ source archive.

    cd mysqldjmx
    ant dist
         

    Then add $TEMP/cmxj/stage/connector-mxj/connector-mxj.jar to the CLASSPATH.

  4. if you have junit, execute the unit tests. From the command line, type:

    java com.mysql.management.AllTestsSuite
        

    The output should look something like this:

    .........................................
    .........................................
    ..........
    Time: 259.438
    
    OK (101 tests)
      

    Note that the tests are a bit slow near the end, so please be patient.

27.5.4. Connector/MXJ Configuration

27.5.4.1. Running as part of the JDBC Driver

A feature of the MySQL Connector/J JDBC driver is the ability to specify a connection to an embedded Connector/MXJ instance through the use of the mxj keyword in the JDBC connection string.

In the following example, we have a program which creates a connection, executes a query, and prints the result to the System.out. The MySQL database will be deployed and started as part of the connection process, and shutdown as part of the finally block.

You can find this file in the Connector/MXJ package as src/ConnectorMXJUrlTestExample.java.

import java.io.File;
import java.sql.Connection;
import java.sql.DriverManager;

import com.mysql.management.driverlaunched.ServerLauncherSocketFactory;
import com.mysql.management.util.QueryUtil;

public class ConnectorMXJUrlTestExample {
  public static String DRIVER = "com.mysql.jdbc.Driver";

  public static String JAVA_IO_TMPDIR = "java.io.tmpdir";

  public static void main(String[] args) throws Exception {
    File ourAppDir = new File(System.getProperty(JAVA_IO_TMPDIR));
    File databaseDir = new File(ourAppDir, "test-mxj");
    int port = Integer.parseInt(System.getProperty("c-mxj_test_port", "3336"));
    String dbName = "our_test_app";

    String url = "jdbc:mysql:mxj://localhost:" + port + "/" + dbName //
      + "?" + "server.basedir=" + databaseDir //
      + "&" + "createDatabaseIfNotExist=true"//
      + "&" + "server.initialize-user=true" //
    ;

    System.out.println(url);

    String userName = "alice";
    String password = "q93uti0opwhkd";

    Class.forName(DRIVER);
    Connection conn = null;
    try {
      conn = DriverManager.getConnection(url, userName, password);
      String sql = "SELECT VERSION()";
      String queryForString = new QueryUtil(conn).queryForString(sql);

      System.out.println("------------------------");
      System.out.println(sql);
      System.out.println("------------------------");
      System.out.println(queryForString);
      System.out.println("------------------------");
      System.out.flush();
      Thread.sleep(100); // wait for System.out to finish flush
    } finally {
      try {
        if (conn != null)
           conn.close();
      } catch (Exception e) {
        e.printStackTrace();
      }

      ServerLauncherSocketFactory.shutdown(databaseDir, null); 
    }
  }
}

To run the above program, be sure to have connector-mxj.jar and Connector/J in the CLASSPATH. Then type:

java ConnectorMXJTestExample
  

27.5.4.2. Running within a Java Object

If you have a java application and wish to “embed” a MySQL database, make use of the com.mysql.management.MysqldResource class directly. This class may be instantiated with the default (no argument) constructor, or by passing in a java.io.File object representing the directory you wish the server to be "unzipped" into. It may also be instantiated with printstreams for "stdout" and "stderr" for logging.

Once instantiated, a java.util.Map, the object will be able to provide a java.util.Map of server options appropriate for the platform and version of MySQL which you will be using.

The MysqldResource enables you to "start" MySQL with a java.util.Map of server options which you provide, as well as "shutdown" the database. The following example shows a simplistic way to embed MySQL in an application using plain java objects.

You can find this file in the Connector/MXJ package as src/ConnectorMXJObjectTestExample.java.

import java.io.File;
import java.sql.Connection;
import java.sql.DriverManager;
import java.util.HashMap;
import java.util.Map;

import com.mysql.management.MysqldResource;
import com.mysql.management.MysqldResourceI;
import com.mysql.management.util.QueryUtil;

public class ConnectorMXJObjectTestExample {
    public static final String DRIVER = "com.mysql.jdbc.Driver";

    public static final String JAVA_IO_TMPDIR = "java.io.tmpdir";

    public static void main(String[] args) throws Exception {
        File ourAppDir = new File(System.getProperty(JAVA_IO_TMPDIR));
        File databaseDir = new File(ourAppDir, "mysql-mxj");
        int port = Integer.parseInt(System.getProperty("c-mxj_test_port",
                "3336"));
        String userName = "alice";
        String password = "q93uti0opwhkd";

        MysqldResource mysqldResource = startDatabase(databaseDir, port,
                userName, password);

        Class.forName(DRIVER);
        Connection conn = null;
        try {
            String dbName = "our_test_app";
            String url = "jdbc:mysql://localhost:" + port + "/" + dbName //
                    + "?" + "createDatabaseIfNotExist=true"//
            ;
            conn = DriverManager.getConnection(url, userName, password);
            String sql = "SELECT VERSION()";
            String queryForString = new QueryUtil(conn).queryForString(sql);

            System.out.println("------------------------");
            System.out.println(sql);
            System.out.println("------------------------");
            System.out.println(queryForString);
            System.out.println("------------------------");
            System.out.flush();
            Thread.sleep(100); // wait for System.out to finish flush
        } finally {
            try {
                if (conn != null) {
                    conn.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            try {
                mysqldResource.shutdown();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    public static MysqldResource startDatabase(File databaseDir, int port,
            String userName, String password) {
        MysqldResource mysqldResource = new MysqldResource(databaseDir);

        Map database_options = new HashMap();
        database_options.put(MysqldResourceI.PORT, Integer.toString(port));
        database_options.put(MysqldResourceI.INITIALIZE_USER, "true");
        database_options.put(MysqldResourceI.INITIALIZE_USER_NAME, userName);
        database_options.put(MysqldResourceI.INITIALIZE_PASSWORD, password);

        mysqldResource.start("test-mysqld-thread", database_options);

        if (!mysqldResource.isRunning()) {
            throw new RuntimeException("MySQL did not start.");
        }

        System.out.println("MySQL is running.");

        return mysqldResource;
    }
}

27.5.4.3. Setting server options

Of course there are many options we may wish to set for a MySQL database. These options may be specified as part of the JDBC connection string simply by prefixing each server option with server.. In the following example we set two driver parameters and two server parameters:

        String url = "jdbc:mysql://" + hostColonPort + "/" 
                + "?"
                + "cacheServerConfiguration=true"
                + "&"
                + "useLocalSessionState=true"
                + "&"
                + "server.basedir=/opt/myapp/db"
                + "&"
                + "server.datadir=/mnt/bigdisk/myapp/data";
  

Starting with Connector/MXJ 5.0.6 you can use the initializer-user property to a connection string. If set to true, the default anonymous and root users will be removed and the user/password combination from the connection URL will be used to create a new user. For example:

        
        String url = "jdbc:mysql:mxj://localhost:" + port
        + "/alice_db"
        + "?server.datadir=" + dataDir.getPath()
        + "&server.initialize-user=true"
        + "&createDatabaseIfNotExist=true"
        ;
      

27.5.5. Connector/MXJ Reference

The following sections include detailed information on the different API interfaces to Connector/MXJ.

27.5.5.1. MysqldResource Constructors

The MysqldResource class supports three different constructor forms:

  • public MysqldResource(File baseDir, File dataDir, String mysqlVersionString, PrintStream out, PrintStream err)

    Enables you to set the base directory, data directory, select a server by its version string, standard out and standard error.

  • public MysqldResource(File baseDir, File dataDir, String mysqlVersionString)

    Enables you to set the base directory, data directory and select a server by its version string. Output for standard out and standard err are directed to System.out and System.err.

  • public MysqldResource(File baseDir, File dataDir)

    Enables you to set the base directory and data directory. The default MySQL version is selected, and output for standard out and standard err are directed to System.out and System.err.

  • public MysqldResource(File baseDir);

    Allows the setting of the "basedir" to deploy the MySQL files to. Output for standard out and standard err are directed to System.out and System.err.

  • public MysqldResource();

    The basedir is defaulted to a subdirectory of the java.io.tempdir. Output for standard out and standard err are directed to System.out and System.err;

27.5.5.2. MysqldResource Methods

MysqldResource API includes the following methods:

  • void start(String threadName, Map mysqldArgs);

    Deploys and starts MySQL. The "threadName" string is used to name the thread which actually performs the execution of the MySQL command line. The map is the set of arguments and their values to be passed to the command line.

  • void shutdown();

    Shuts down the MySQL instance managed by the MysqldResource object.

  • Map getServerOptions();

    Returns a map of all the options and their current (or default, if not running) options available for the MySQL database.

  • boolean isRunning();

    Returns true if the MySQL database is running.

  • boolean isReadyForConnections();

    Returns true once the database reports that is ready for connections.

  • void setKillDelay(int millis);

    The default “Kill Delay” is 30 seconds. This represents the amount of time to wait between the initial request to shutdown and issuing a “force kill” if the database has not shutdown by itself.

  • void addCompletionListenser(Runnable listener);

    Allows for applications to be notified when the server process completes. Each ''listener'' will be fired off in its own thread.

  • String getVersion();

    Returns the version of MySQL.

  • void setVersion(int MajorVersion, int minorVersion, int patchLevel);

    The standard distribution comes with only one version of MySQL packaged. However, it is possible to package multiple versions, and specify which version to use.

27.5.6. Connector/MXJ Notes and Tips

This section contains notes and tips on using the Connector/MXJ component within your applications.

27.5.6.1. Creating your own Connector/MXJ Package

If you want to create a custom Connector/MXJ package that includes a specific mysqld version or platform then you must extract and rebuild the mysql-connector-mxj.jar (Connector/MXJ v5.0.3 or earlier) or mysql-connector-mxj-gpl-[ver]-db-files.jar (Connector/MXJ v5.0.4 or later) file.

First, you should create a new directory into which you can extract the current connector-mxj.jar:

shell> mkdir custom-mxj
shell> cd custom-mxj
shell> jar -xf connector-mxj.jar
shell> ls
5-0-22/
ConnectorMXJObjectTestExample.class
ConnectorMXJUrlTestExample.class
META-INF/
TestDb.class
com/
kill.exe

If you are using Connector/MXJ v5.0.4 or later, you should unpack the connector-mxj-db-files.jar:

shell> mkdir custom-mxj
shell> cd custom-mxj
shell> jar -xf connector-mxj-db-files.jar
shell> ls
5-0-51a/                         
META-INF/                       
connector-mxj.properties

The MySQL version directory, 5-0-22 or 5-0-51a in the preceding examples, contains all of the files used to create an instance of MySQL when Connector/MXJ is executed. All of the files in this directory are required for each version of MySQL that you want to embed. Note as well the format of the version number, which uses hyphens instead of periods to separate the version number components.

Within the version specific directory are the platform specific directories, and archives of the data and share directory required by MySQL for the various platforms. For example, here is the listing for the default Connector/MXJ package:

shell>> ls
Linux-i386/
META-INF/
Mac_OS_X-ppc/
SunOS-sparc/
Win-x86/
com/
data_dir.jar
share_dir.jar
win_share_dir.jar

Platform specific directories are listed by their OS and platform - for example the mysqld for Mac OS X PowerPC is located within the Mac_OS_X-ppc directory. You can delete directories from this location that you do not require, and add new directories for additional platforms that you want to support.

To add a platform specific mysqld, create a new directory with the corresponding name for your operating system/platform. For example, you could add a directory for Mac OS X/Intel using the directory Mac_OS_X-i386.

On Unix systems, you can determine the platform using uname:

shell> uname -p
i386

In Connector/MXJ v5.0.9 and later, an additional platform-map.properties file is used to associate a specific platform and operating system combination with the directory in which the mysqld for that combination is located. The determined operating system and platform are on the left, and the directory name where the appropriate mysqld is located is on the right. You can see a sample of the file below:

Linux-i386=Linux-i386
Linux-x86=Linux-i386
Linux-i686=Linux-i386
Linux-x86_64=Linux-i386
Linux-ia64=Linux-i386

#Linux-ppc=Linux-ppc
#Linux-ppc64=Linux-ppc

Mac_OS_X-i386=Mac_OS_X-i386
Mac_OS_X-ppc=Mac_OS_X-ppc
Rhapsody-PowerPC=Mac_OS_X-ppc
#Mac_OS-PowerPC=
#macos-PowerPC=
#MacOS-PowerPC=

SunOS-sparc=SunOS-sparc
Solaris-sparc=SunOS-sparc
SunOS-x86=SunOS-x86
Solaris-x86=SunOS-x86

FreeBSD-x86=FreeBSD-x86

Windows_Vista-x86=Win-x86
Windows_2003-x86=Win-x86
Windows_XP-x86=Win-x86
Windows_2000-x86=Win-x86
Windows_NT-x86=Win-x86
Windows_NT_(unknown)-x86=Win-x86
      

Now you need to download or compile mysqld for the MySQL version and platform you want to include in your custom connector-mxj.jar package into the new directory.

Create a file called version.txt in the OS/platform directory you have just created that contains the version string/path of the mysqld binary. For example:

mysql-5.0.22-osx10.3-i386/bin/mysqld

You can now recreate the connector-mxj.jar file with the added mysqld:

shell> cd custom-mxj
shell> jar -cf ../connector-mxj.jar *

For Connector/MXJ v5.0.4 and later, you should repackage to the connector-mxj-db-files.jar:

shell> cd custom-mxj
shell> jar -cf ../mysql-connector-mxj-gpl-[ver]-db-files.jar *

You should test this package using the steps outlined in Section 27.5.3.3, “Connector/MXJ Quick Start Guide”.

Note

Because the mysql-connector-mxj-gpl-[ver]-db-files.jar file is separate from the main Connector/MXJ classes you can distribute different mysql-connector-mxj-gpl-[ver]-db-files.jar files to different hotsts or for different projects without having to create a completely new main mysql-connector-mxj-gpl-[ver].jar file for each one.

27.5.6.2. Deploying Connector/MXJ with a pre-configured database

To include a pre-configured/populated database within your Connector/MXJ JAR file you must create a custom data_dir.jar file, as included within the main connector-mxj.jar (Connector/MXJ 5.0.3 or earlier) or mysql-connector-mxj-gpl-[ver]-db-files.jar (Connector/MXJ 5.0.4 or later) file:

  1. First extract the connector-mxj.jar or mysql-connector-gpl-[ver]-db-files.jar file, as outlined in the previous section (see Section 27.5.6.1, “Creating your own Connector/MXJ Package”).

  2. First, create your database and populate the database with the information you require in an existing instance of MySQL - including Connector/MXJ instances. Data file formats are compatible across platforms.

  3. Shutdown the instance of MySQL.

  4. Create a JAR file of the data directory and databases that you want to include your Connector/MXJ package. You should include the mysql database, which includes user authentication information, in addition to the specific databases you want to include. For example, to create a JAR of the mysql and mxjtest databases:

    shell> jar -cf ../data_dir.jar mysql mxjtest
  5. For Connector/MXJ 5.0.3 or earlier, copy the data_dir.jar file into the extracted connector-mxj.jar directory, and then create an archive for connector-mxj.jar.

    For Connector/MXJ 5.0.4 or later, copy the data_dir.jar file into the extracted mysql-connector-mxj-gpl-[ver]-db-files.jar directory, and then create an archive for mysql-connector-mxj-db-gpl-[ver]--files.jar.

Note that if you are create databases using the InnoDB engine, you must include the ibdata.* and ib_logfile* files within the data_dir.jar archive.

27.5.6.3. Running within a JMX Agent (custom)

As a JMX MBean, MySQL Connector/MXJ requires a JMX v1.2 compliant MBean container, such as JBoss version 4. The MBean will uses the standard JMX management APIs to present (and allow the setting of) parameters which are appropriate for that platform.

If you are not using the SUN Reference implementation of the JMX libraries, you should skip this section. Or, if you are deploying to JBoss, you also may wish to skip to the next section.

We want to see the MysqldDynamicMBean in action inside of a JMX agent. In the com.mysql.management.jmx.sunri package is a custom JMX agent with two MBeans:

  1. the MysqldDynamicMBean, and

  2. a com.sun.jdmk.comm.HtmlAdaptorServer, which provides a web interface for manipulating the beans inside of a JMX agent.

When this very simple agent is started, it will allow a MySQL database to be started and stopped with a web browser.

  1. Complete the testing of the platform as above.

    • current JDK, JUnit, Connector/J, MySQL Connector/MXJ

    • this section requires the SUN reference implementation of JMX

    • PATH, JAVA_HOME, ANT_HOME, CLASSPATH

  2. If not building from source, skip to next step

    rebuild with the "sunri.present"

    ant -Dsunri.present=true dist 
    re-run tests:
    java junit.textui.TestRunner com.mysql.management.AllTestsSuite
    
  3. launch the test agent from the command line:

    java com.mysql.management.jmx.sunri.MysqldTestAgentSunHtmlAdaptor &
         
  4. from a browser:

    http://localhost:9092/
         
  5. under MysqldAgent,

    select "name=mysqld"
         
  6. Observe the MBean View

  7. scroll to the bottom of the screen press the startMysqld button

  8. click Back to MBean View

  9. scroll to the bottom of the screen press stopMysqld button

  10. kill the java process running the Test Agent (jmx server)

27.5.6.4. Deployment in a standard JMX Agent environment (JBoss)

Once there is confidence that the MBean will function on the platform, deploying the MBean inside of a standard JMX Agent is the next step. Included are instructions for deploying to JBoss.

  1. Ensure a current version of java development kit (v1.4.x), see above.

    • Ensure JAVA_HOME is set (JBoss requires JAVA_HOME)

    • Ensure JAVA_HOME/bin is in the PATH (You will NOT need to set your CLASSPATH, nor will you need any of the jars used in the previous tests).

  2. Ensure a current version of JBoss (v4.0RC1 or better)

    http://www.jboss.org/index.html
    select "Downloads"
    select "jboss-4.0.zip"
    pick a mirror
    unzip ~/dload/jboss-4.0.zip
    create a JBOSS_HOME environment variable set to the unzipped directory
    unix only:
    cd $JBOSS_HOME/bin
    chmod +x *.sh
    
  3. Deploy (copy) the connector-mxj.jar to $JBOSS_HOME/server/default/lib.

  4. Deploy (copy) mysql-connector-java-3.1.4-beta-bin.jar to $JBOSS_HOME/server/default/lib.

  5. Create a mxjtest.war directory in $JBOSS_HOME/server/default/deploy.

  6. Deploy (copy) index.jsp to $JBOSS_HOME/server/default/deploy/mxjtest.war.

  7. Create a mysqld-service.xml file in $JBOSS_HOME/server/default/deploy.

    <?xml version="1.0" encoding="UTF-8"?>
     <server>
      <mbean code="com.mysql.management.jmx.jboss.JBossMysqldDynamicMBean"
         name="mysql:type=service,name=mysqld">
      <attribute name="datadir">/tmp/xxx_data_xxx</attribute>
      <attribute name="autostart">true</attribute>
      </mbean>
     </server>
         
  8. Start jboss:

    • on unix: $JBOSS_HOME/bin/run.sh

    • on windows: %JBOSS_HOME%\bin\run.bat

    Be ready: JBoss sends a lot of output to the screen.

  9. When JBoss seems to have stopped sending output to the screen, open a web browser to: http://localhost:8080/jmx-console

  10. Scroll down to the bottom of the page in the mysql section, select the bulleted mysqld link.

  11. Observe the JMX MBean View page. MySQL should already be running.

  12. (If "autostart=true" was set, you may skip this step.) Scroll to the bottom of the screen. You may press the Invoke button to stop (or start) MySQL observe Operation completed successfully without a return value. Click Back to MBean View

  13. To confirm MySQL is running, open a web browser to http://localhost:8080/mxjtest/ and you should see that

    SELECT 1

    returned with a result of

    1
  14. Guided by the $JBOSS_HOME/server/default/deploy/mxjtest.war/index.jsp you will be able to use MySQL in your Web Application. There is a test database and a root user (no password) ready to experiment with. Try creating a table, inserting some rows, and doing some selects.

  15. Shut down MySQL. MySQL will be stopped automatically when JBoss is stopped, or: from the browser, scroll down to the bottom of the MBean View press the stop service Invoke button to halt the service. Observe Operation completed successfully without a return value. Using ps or task manager see that MySQL is no longer running

As of 1.0.6-beta version is the ability to have the MBean start the MySQL database upon start up. Also, we've taken advantage of the JBoss life-cycle extension methods so that the database will gracefully shut down when JBoss is shutdown.

27.5.7. Connector/MXJ Support

There are a wide variety of options available for obtaining support for using Connector/MXJ. You should contact the Connector/MXJ community for help before reporting a potential bug or problem. See Section 27.5.7.1, “Connector/MXJ Community Support”.

27.5.7.1. Connector/MXJ Community Support

MySQL AB provides assistance to the user community by means of a number of mailing lists and web based forums.

You can find help and support through the MySQL and Java mailing list.

For information about subscribing to MySQL mailing lists or to browse list archives, visit http://lists.mysql.com/. See Section 1.6.1, “MySQL Mailing Lists”.

Community support from experienced users is also available through the MyODBC Forum. You may also find help from other users in the other MySQL Forums, located at http://forums.mysql.com. See Section 1.6.2, “MySQL Community Support at the MySQL Forums”.

27.5.7.2. How to Report Connector/MXJ Problems

If you encounter difficulties or problems with Connector/MXJ, contact the Connector/MXJ community Section 27.5.7.1, “Connector/MXJ Community Support”.

If reporting a problem, you should ideally include the following information with the email:

  • Operating system and version

  • Connector/MXJ version

  • MySQL server version

  • Copies of error messages or other unexpected output

  • Simple reproducible sample

Remember that the more information you can supply to us, the more likely it is that we can fix the problem.

If you believe the problem to be a bug, then you must report the bug through http://bugs.mysql.com/.

27.5.7.3. Connector/MXJ Change History

The Connector/MXJ Change History (Changelog) is located with the main Changelog for MySQL. See Section E.7, “MySQL Connector/MXJ Change History”.

27.6. Connector/PHP

The PHP distribution and documentation are available from the PHP Web site. MySQL provides the mysql and mysqli extensions for the Windows operating system on http://dev.mysql.com/downloads/connector/php/ for MySQL version 4.1.16 and higher, MySQL 5.0.18, and MySQL 5.1. You can find information why you should preferably use the extensions provided by MySQL on that page. For platforms other than Windows, you should use the mysql or mysqli extensions shipped with the PHP sources. See Section 26.3, “MySQL PHP API”.