Глава 21. Connectors and APIs

Содержание

21.1. MySQL Connector/ODBC
21.1.1. Connector/ODBC Versions
21.1.2. Connector/ODBC Introduction
21.1.3. Connector/ODBC Installation
21.1.4. Connector/ODBC Configuration
21.1.5. Connector/ODBC Examples
21.1.6. Connector/ODBC Reference
21.1.7. Connector/ODBC Notes and Tips
21.1.8. Connector/ODBC Support
21.2. MySQL Connector/Net
21.2.1. Connector/Net Versions
21.2.2. Connector/Net Installation
21.2.3. Connector/Net Visual Studio Integration
21.2.4. Connector/Net Tutorials
21.2.5. Connector/Net Programming
21.2.6. Connector/Net Connection String Options Reference
21.2.7. Connector/Net API Reference
21.2.8. Connector/Net Support
21.2.9. Connector/Net FAQ
21.3. MySQL Connector/J
21.3.1. Overview of MySQL Connector/J
21.3.2. Connector/J Versions
21.3.3. Connector/J Installation
21.3.4. Connector/J Examples
21.3.5. Connector/J (JDBC) Reference
21.3.6. JDBC Concepts
21.3.7. J2EE Concepts
21.3.8. Using Connector/J with Tomcat
21.3.9. Using Connector/J with JBoss
21.3.10. Using Connector/J with Spring
21.3.11. Using Connector/J with GlassFish
21.3.12. Troubleshooting Connector/J
21.3.13. Connector/J Support
21.4. MySQL Connector/MXJ
21.4.1. Overview of Connector/MXJ
21.4.2. Connector/MXJ Versions
21.4.3. Connector/MXJ Installation
21.4.4. Connector/MXJ Configuration
21.4.5. Connector/MXJ Reference
21.4.6. Connector/MXJ Notes and Tips
21.4.7. Connector/MXJ Samples
21.4.8. Connector/MXJ Support
21.5. MySQL Connector/C++
21.5.1. Installing the MySQL Connector/C++ Binary
21.5.2. Installing MySQL Connector/C++ from Source
21.5.3. MySQL Connector/C++ Building Windows Applications with Microsoft Visual Studio
21.5.4. MySQL Connector/C++ Building Linux Applications with NetBeans
21.5.5. MySQL Connector/C++ Getting Started: Usage Examples
21.5.6. MySQL Connector/C++ Tutorials
21.5.7. MySQL Connector/C++ Debug Tracing
21.5.8. MySQL Connector/C++ Usage Notes
21.5.9. MySQL Connector/C++ Known Bugs and Issues
21.5.10. MySQL Connector/C++ Feature requests
21.5.11. MySQL Connector/C++ Support
21.5.12. MySQL Connector/C++ FAQ
21.6. MySQL Connector/C
21.6.1. Building MySQL Connector/C from the Source Code
21.6.2. Testing MySQL Connector/C
21.6.3. MySQL Connector/C FAQ
21.7. MySQL Connector/OpenOffice.org
21.7.1. Installation
21.7.2. Getting Started: Connecting to MySQL
21.7.3. Getting Started: Usage Examples
21.7.4. References
21.7.5. Known Bugs
21.7.6. Contact
21.8. libmysqld, the Embedded MySQL Server Library
21.8.1. Compiling Programs with libmysqld
21.8.2. Restrictions When Using the Embedded MySQL Server
21.8.3. Options with the Embedded Server
21.8.4. Embedded Server Examples
21.8.5. Licensing the Embedded Server
21.9. MySQL C API
21.9.1. C API Data Structures
21.9.2. C API Function Overview
21.9.3. C API Function Описаниеs
21.9.4. C API Prepared Statements
21.9.5. C API Prepared Statement Data Structures
21.9.6. C API Prepared Statement Function Overview
21.9.7. C API Prepared Statement Function Описаниеs
21.9.8. C API Threaded Function Описаниеs
21.9.9. C API Embedded Server Function Описаниеs
21.9.10. C API Client Plugin Functions
21.9.11. Common Questions and Problems When Using the C API
21.9.12. Controlling Automatic Reconnection Behavior
21.9.13. C API Support for Multiple Statement Execution
21.9.14. C API Prepared Statement Problems
21.9.15. C API Prepared Statement Handling of Date and Time Values
21.9.16. C API Support for Prepared CALL Statements
21.9.17. Building Client Programs
21.10. MySQL PHP API
21.10.1. Original MySQL API (Mysql)
21.10.2. MySQL Improved Extension (Mysqli)
21.10.3. MySQL Native Driver (Mysqlnd)
21.10.4. MySQL Functions (PDO_MYSQL) (MySQL (PDO))
21.10.5. Connector/PHP
21.10.6. Common Problems with MySQL and PHP
21.10.7. Enabling Both mysql and mysqli in PHP
21.11. MySQL Perl API
21.12. MySQL Python API
21.13. MySQL Ruby APIs
21.13.1. The MySQL/Ruby API
21.13.2. The Ruby/MySQL API
21.14. MySQL Tcl API
21.15. MySQL Eiffel Wrapper

MySQL Connectors provide connectivity to the MySQL server for client programs. APIs provide low-level access to the MySQL protocol and MySQL resources. Both Connectors and the APIs enable you to connect and execute MySQL statements from another language or environment, including Java (JDBC), ODBC, Perl, Python, PHP, Ruby, and native C and embedded MySQL instances.

Замечание

Connector version numbers do not correlate with MySQL Server version numbers. See also Table 21.2, “MySQL Connector Versions and MySQL Server Versions”.

A number of connectors are developed by MySQL:

  • Connector/ODBC provides driver support for connecting to a MySQL server using the Open Database Connectivity (ODBC) API. Support is available for ODBC connectivity from Windows, Unix and Mac OS X platforms.

  • Connector/Net enables developers to create .NET applications that use data stored in a MySQL database. Connector/Net implement a fully functional ADO.NET interface and provides support for use with ADO.NET aware tools. Applications that want to use Connector/Net can be written in any of the supported .NET languages.

    The MySQL Visual Studio Plugin works with Connector/Net and Visual Studio 2005. The plugin is a MySQL DDEX Provider, which means that you can use the schema and data manipulation tools within Visual Studio to create and edit objects within a MySQL database.

  • Connector/J provides driver support for connecting to MySQL from a Java application using the standard Java Database Connectivity (JDBC) API.

  • Connector/MXJ is a tool that enables easy deployment and management of MySQL server and database through your Java application.

  • Connector/C++ is a tool that enables easy deployment and management of MySQL server and database through your C++ application.

  • Connector/C is a standalone replacement for the MySQL Client Library (libmysql).

  • Connector/OpenOffice.org is a tool that enables OpenOffice.org applications to connect to MySQL server.

There are two direct access methods for using MySQL natively within a C application:

  • The C API provides low-level access to the MySQL protocol through the libmysql client library; this is the primary method used to connect to an instance of the MySQL server, and is used both by MySQL command line clients and many of the APIs also detailed in this section. MySQL Connector/C can now also be used for this purpose.

  • libmysqld is an embedded MySQL server library that enables you to embed an instance of the MySQL server into your C applications.

If you need to access MySQL from a C application, or build an interface to MySQL for a language not supported by the Connectors or APIs in this chapter, the C API is where you would start. A number of programmers utilities are available to help with the process, and also covered in this section.

The remaining APIs provide an interface to MySQL from specific application languages. These solutions are not developed or supported by MySQL. Basic information on their usage and abilities is provided here for reference purposes only.

All the language APIs are developed using one of two methods, using libmysql or by building a native driver. The two solutions offer different benefits:

  • Using libmysql offers complete compatibility with MySQL as it uses the same libraries as the MySQL client applications. However, the feature set is limited to the implementation and interfaces exposed through libmysql and the performance may be lower as data is copied between the native language, and the MySQL API components. MySQL Connector/C is a possible alternative to using libmysql.

  • Native drivers are an implementation of the MySQL network protocol entirely within the host language or environment. Native drivers are fast, as there is less copying of data between components, and they can offer advanced functionality not available through the standard MySQL API. Native drivers are also easier to build and deploy, as you do not need a copy of the MySQL client libraries to build the native driver components.

A list of many of the libraries and interfaces available for MySQL are shown in the table. See Table 21.1, “MySQL APIs and Interfaces”.

Table 21.1. MySQL APIs and Interfaces

EnvironmentAPITypeNotes
AdaMySQL Bindings for GNU AdalibmysqlSee MySQL Bindings for GNU Ada
CConnector/CReplacement for libmysqlSee Section 21.6, “MySQL Connector/C”.
C++Connector/C++libmysqlSee Section 21.5, “MySQL Connector/C++”.
 MySQL++libmysqlSee MySQL++ Web site.
 MySQL wrappedlibmysqlSee MySQL wrapped.
CocoaMySQL-CocoalibmysqlCompatible with the Objective-C Cocoa environment. See http://mysql-cocoa.sourceforge.net/
DMySQL for DlibmysqlSee MySQL for D.
EiffelEiffel MySQLlibmysqlSee Section 21.15, “MySQL Eiffel Wrapper”.
Erlangerlang-mysql-driverlibmysqlSee erlang-mysql-driver.
HaskellHaskell MySQL BindingsNative DriverSee Brian O'Sullivan's pure Haskell MySQL bindings.
 hsql-mysqllibmysqlSee MySQL driver for Haskell .
Java/JDBCConnector/JNative DriverSee Section 21.3, “MySQL Connector/J”.
KayaMyDBlibmysqlSee MyDB.
LuaLuaSQLlibmysqlSee LuaSQL.
.NET/MonoConnector/NetNative DriverSee Section 21.2, “MySQL Connector/Net”.
Objective CamlMySQL Bindings for OBjective CamllibmysqlSee MySQL Bindings for Objective Caml.
OctaveDatabase bindings for GNU OctavelibmysqlSee Database bindings for GNU Octave.
ODBCConnector/ODBClibmysqlSee Section 21.1, “MySQL Connector/ODBC”.
OpenOfficeMySQL Connector/OpenOffice.orglibmysqlDirect connectivity, without using JDBC/ODBC. See Section 21.7, “MySQL Connector/OpenOffice.org”.
PerlDBI/DBD::mysqllibmysqlSee Section 21.11, “MySQL Perl API”.
 Net::MySQLNative DriverSee Net::MySQL at CPAN
PHPmysql, ext/mysql interface (deprecated)libmysqlSee Section 21.10.1, “Original MySQL API (Mysql)”.
 mysqli, ext/mysqli interfacelibmysqlSee Section 21.10.2, “MySQL Improved Extension (Mysqli)”.
 PDO_MYSQLlibmysqlSee Section 21.10.4, “MySQL Functions (PDO_MYSQL) (MySQL (PDO))”.
 PDO mysqlndNative DriverSee PHP PDO mysqlnd.
PythonMySQLdblibmysqlSee Section 21.12, “MySQL Python API”.
RubyMySQL/RubylibmysqlUses libmysql. See Section 21.13.1, “The MySQL/Ruby API”.
 Ruby/MySQLNative DriverSee Section 21.13.2, “The Ruby/MySQL API”.
SchemeMyscshlibmysqlSee Myscsh.
SPLsql_mysqllibmysqlSee sql_mysql for SPL.
TclMySQLtcllibmysqlSee Section 21.14, “MySQL Tcl API”.

Table 21.2. MySQL Connector Versions and MySQL Server Versions

ConnectorConnector versionMySQL Server version
Connector/C++1.0.5 GA5.6, 5.5, 5.4, 5.1
Connector/J5.1.85.6, 5.5, 5.4, 5.1, 5.0, 4.1
Connector/Net6.55.6, 5.5, 5.4, 5.1, 5.0
Connector/Net6.45.6, 5.5, 5.4, 5.1, 5.0
Connector/Net6.35.6, 5.5, 5.4, 5.1, 5.0
Connector/Net6.2 (No longer supported)5.6, 5.5, 5.4, 5.1, 5.0
Connector/Net6.1 (No longer supported)5.6, 5.5, 5.4, 5.1, 5.0
Connector/Net6.0 (No longer supported)5.6, 5.5, 5.4, 5.1, 5.0
Connector/Net5.2 (No longer supported)5.6, 5.5, 5.4, 5.1, 5.0
Connector/Net1.0 (No longer supported)5.0, 4.0
Connector/ODBC5.15.6, 5.5, 5.4, 5.1, 5.0, 4.1.1+
Connector/ODBC3.51 (Unicode not supported)5.6, 5.5, 5.4, 5.1, 5.0, 4.1
Connector/OpenOffice.org1.0 GA5.6, 5.5, 5.4, 5.1, 5.0

21.1. 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, with 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 section of the ODBC API reference assumes a good working knowledge of C, general DBMS, and a 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 connector/ODBC topics include:

21.1.1. 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 with MySQL versions 4.1.1 and newer.

    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 data type, and support for Unicode login, password and DSN configurations. For more information,. see Microsoft Knowledgebase Article #716246.

    • Support for the SQL_NUMERIC_STRUCT data type, 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) 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.

Замечание

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

Замечание

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.

21.1.2. 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 enables 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.

21.1.2.1. 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 21.1.6.1, “Connector/ODBC API Reference”. For general information about ODBC, see http://support.microsoft.com/kb/110093.

21.1.2.1.1. 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 21.1.4, “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).

21.1.2.1.2. 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.

21.1.3. 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. Use the source installation methods 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

You can get a copy of the latest version of Connector/ODBC binaries and sources from our Web site at http://dev.mysql.com/downloads/connector/odbc/.

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, 2003, Vista and 7

  • 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.

Замечание

On all non-Windows platforms except Mac OS X, the driver is built against unixODBC and is expecting a 2-byte SQLWCHAR, not 4 bytes as iODBC is using. For this reason, the binaries are only compatible with unixODBC and you will need to recompile the driver against iODBC to use them together. For further information see Section 21.1.2.1.2, “ODBC Driver Managers”.

For further instructions:

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

Before installing the Connector/ODBC drivers on Windows, 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.

Замечание

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

21.1.3.1.1. 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.

Follow these steps to complete the installation:

  1. Double-click 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 След. 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 След. and then proceed to step 5.

    You can also choose a Custom installation, which enables you to select the individual components to install. You have chosen this method, click След. 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 След. 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 21.1.4, “Connector/ODBC Configuration”.

21.1.3.1.2. 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.

Замечание

The following instructions will only work for 32-bit Windows systems. If you have a 64-bit Windows system you are advised to use the MSI installer, which will install both the 32-bit and 64-bit drivers to the correct 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.

Замечание

Changing or adding a new DSN (data source name) may be accomplished using either the GUI, or from the command-line using myodbc3i.exe with Connector/ODBC 3.51, or myodbc-installer.exe with Connector/ODBC 5.1.

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 nonstandard 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.

21.1.3.2. 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.

Замечание

To install Connector/ODBC 5.1 on Unix you require unixODBC 2.2.12 or later to be installed.

21.1.3.2.1. 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 file and execute these commands.

Then proceed on to Section 21.1.4.5, “Configuring a Connector/ODBC DSN on Unix”, to configure the DSN for Connector/ODBC. For more information, refer to the INSTALL file that comes with your distribution.

21.1.3.2.2. 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 21.1.4.5, “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

21.1.3.3. 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 lets you connect to MySQL databases on any platform through the ODBC interface. If your application requires an ODBC interface, install the Connector/ODBC driver. 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 compressed 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:

    shell> 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:

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

    shell> 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:

shell> 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 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

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

You only need to install Connector/ODBC from source on Windows 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 21.1.3.1, “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.

    Microsoft Visual Studio 7 and 8 are preferred, and well-tested.

  • Connector/ODBC 5.1: CMake.

    Connector/ODBC 3.51: A 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/.

21.1.3.4.1. Building Connector/ODBC 5.1

You need to have the environment variables set for the Visual Studio toolchain. Visual Studio includes a batch file to set these for you, and installs a Start menu shortcut that opens a command prompt with these variables set.

You need to set MYSQL_DIR to the MySQL server installation path, while using the short-style file names. For example:

C:\> set MYSQL_DIR=C:\PROGRA~1\MySQL\MYSQLS~1.0

Build Connector/ODBC using the "cmake" command-line tool by executing the following from the source root directory (in a command prompt window):

C:\> cmake -G "Visual Studio 8 2005"

This produces a project file that you can open with Visual Studio, or build from the command line with either of the following commands:

C:\> devenv.com MySQL_Connector_ODBC.sln /build Release
C:\> devenv.com MySQL_Connector_ODBC.sln /build RelWithDebInfo

To compile the "Debug" build, you must set the cmake build type so that the correct version of the MySQL client libraries are used:

C:\> cmake -G "Visual Studio 8 2005" -DCMAKE_BUILD_TYPE=Debug
C:\> devenv.com MySQL_Connector_ODBC.sln /build Debug

Upon completion, you will find the executables in the bin/ and lib/ sub-directories.

See Section 21.1.3.1.2, “Installing the Windows Connector/ODBC Driver using the Zipped DLL package” to complete the installation.

21.1.3.4.2. 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
    
Замечание
  • 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*.

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

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

Замечание

As of Connector/5.1.9, the build system on Linux changed, and now uses CMake instead of autoconf (configure). The manual refers to both methods.

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

  • A working ANSI C++ compiler. GCC 4.2.1 or later, Sun Studio 10 or later, Visual Studio 2008 or later, and many current vendor-supplied compilers are known to work.

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

  • CMake, as of Connector/ODBC 5.1.9.

  • 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 or client libraries from source using the GNU autotools, you must use the --enable-thread-safe-client option to configure when the libraries were built. No special option is needed if you configure with CMake.

    Also, ensure that the libmysqlclient library was 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 21.1.2.1.2, “ODBC Driver Managers”, for more information.

  • If you are using a character set that isn't compiled into the MySQL client library, 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.

21.1.3.5.1. Typical cmake Options

CMake support on Unix exists as of Connector/ODBC 5.1.9.

iODBC is the default ODBC library used by Connector/ODBC. Alternatively, unixODBC may be used by passing in the appropriate option to CMake. For example:

shell> cmake -G "Unix Makefiles" -DWITH_UNIXODBC=1

When you run cmake, you might add options to the command line. Here are some examples:

21.1.3.5.2. Typical configure Options

autoconf (configure) is supported on Unix in Connector/ODBC 5.1.8 and below.

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 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
21.1.3.5.3. 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. 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 nondebugging versions (configured with --without-debug).

    To enable debugging information, build the driver from a source distribution with the proper configuration option to enable debugging support. See Section 2.9.4, “MySQL Source-Configuration Options”.

  • 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
21.1.3.5.4. 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.

21.1.3.5.5. 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
21.1.3.5.6. 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.

21.1.3.5.7. 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.

21.1.3.5.8. 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
21.1.3.5.9. 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.

21.1.3.5.10. 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
Замечание

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'.

21.1.3.6. Installing Connector/ODBC from the Development Source Tree

Caution

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

To obtain the most recent development source tree, first download and install Bazaar from the Bazaar VCS Web site. Bazaar is supported by any platform that supports Python, and is therefore compatible with any Linux, Unix, Windows or Mac OS X host. Instructions for downloading and installing Bazaar on the different platforms are available on the Bazaar Web site.

Build from the source trees requires 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 check out 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> bzr branch lp:myodbc

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 myodbc
shell> aclocal
shell> autoheader
shell> libtoolize -c -f
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 21.1.3.5.2, “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 21.1.3.4, “Installing Connector/ODBC from a Source Distribution on Windows”.

After the initial checkout operation to get the source tree, run bzr pull periodically to update your source according to the latest version.

21.1.4. 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.

21.1.4.1. 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
  • Host Name
  • 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.

21.1.4.2. 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 check boxes. 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.

Table 21.3. Connector/ODBC DSN Configuration Options

ParameterDefault ValueComment
userODBCThe user name used to connect to MySQL.
uidODBCSynonymous with user. Added in 3.51.16.
serverlocalhostThe host name of the MySQL server.
database The default database.
option0Options that specify how Connector/ODBC works. See below.
port3306The TCP/IP port to use if server is not localhost.
initstmt Initial statement. A statement to execute when connecting to MySQL. In version 3.51 the parameter is called stmt. Note, the driver supports the initial statement being executed only at the time of the initial connection.
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 permissible 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 behavior is to ignore SSL certificate verification.
readtimeout The timeout in seconds for attempts to read from the server. Each attempt uses this timeout value and there are retries if necessary, so the total effective timeout value is three times the option value. You can set the value so that a lost connection can be detected earlier than the TCP/IP Close_Wait_Timeout value of 10 minutes. This option works only for TCP/IP connections, and only for Windows prior to MySQL 5.1.12. Corresponds to the MYSQL_OPT_READ_TIMEOUT option of the MySQL Client Library. This option was added in Connector/ODBC 3.51.27.
writetimeout The timeout in seconds for attempts to write to the server. Each attempt uses this timeout value and there are net_retry_count retries if necessary, so the total effective timeout value is net_retry_count times the option value. This option works only for TCP/IP connections, and only for Windows prior to MySQL 5.1.12. Corresponds to the MYSQL_OPT_WRITE_TIMEOUT option of the MySQL Client Library. This option was added in Connector/ODBC 3.51.27.
interactive Enables the CLIENT_INTERACTIVE connection option of mysql_real_connect.
Замечание

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 check boxes 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.

Table 21.4. Connector/ODBC Option Flags

Flag NameGUI OptionConstant ValueОписание
FLAG_FIELD_LENGTHDo not Optimize Column Width The client cannot handle that Connector/ODBC returns the real width of a column. This option was removed in 3.51.18.
FLAG_FOUND_ROWSReturn Matching Rows2The client cannot 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.
FLAG_DEBUGTrace Driver Calls To myodbc.log Make 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.
FLAG_BIG_PACKETSAllow Big Results8Do not set any packet limit for results and bind parameters. Without this option, parameter binding will be truncated to 255 characters.
FLAG_NO_PROMPTDo not Prompt Upon Connect16Do not prompt for questions even if driver would like to prompt.
FLAG_DYNAMIC_CURSOREnable Dynamic Cursor32Enable or disable the dynamic cursor support.
FLAG_NO_SCHEMAIgnore # in Table Name64Ignore use of database name in db_name.tbl_name.col_name.
FLAG_NO_DEFAULT_CURSORUser Manager Cursors128Force use of ODBC manager cursors (experimental).
FLAG_NO_LOCALEDo not Use Set Locale256Disable the use of extended fetch (experimental).
FLAG_PAD_SPACEPad Char To Full Length512Pad CHAR columns to full column length.
FLAG_FULL_COLUMN_NAMESReturn Table Names for SQLDescribeCol1024SQLDescribeCol() returns fully qualified column names.
FLAG_COMPRESSED_PROTOUse Compressed Protocol2048Use the compressed client/server protocol.
FLAG_IGNORE_SPACEIgnore Space After Function Names4096Tell server to ignore space after function name and before “(” (needed by PowerBuilder). This makes all function names keywords.
FLAG_NAMED_PIPEForce Use of Named Pipes8192Connect with named pipes to a mysqld server running on NT.
FLAG_NO_BIGINTChange BIGINT Columns to Int16384Change BIGINT columns to INT columns (some applications cannot handle BIGINT).
FLAG_NO_CATALOGNo Catalog32768Forces results from the catalog functions, such as SQLTables, to always return NULL and the driver to report that catalogs are not supported.
FLAG_USE_MYCNFRead Options From my.cnf65536Read parameters from the [client] and [odbc] groups from my.cnf.
FLAG_SAFESafe131072Add some extra safety checks.
FLAG_NO_TRANSACTIONSDisable transactions262144Disable transactions.
FLAG_LOG_QUERYSave queries to myodbc.sql524288Enable query logging to c:\myodbc.sql(/tmp/myodbc.sql) file. (Enabled only in debug mode.)
FLAG_NO_CACHEDo not Cache Result (forward only cursors)1048576Do 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 do not want the driver to cache the entire result set.
FLAG_FORWARD_CURSORForce Use Of Forward Only Cursors2097152Force 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 noncache result sets, then this option ensures the forward-only cursor behavior.
FLAG_AUTO_RECONNECTEnable auto-reconnect.4194304Enables auto-reconnection functionality. Do 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.
FLAG_AUTO_IS_NULLFlag Auto Is Null8388608

When FLAG_AUTO_IS_NULL is set, the driver does not change the default value of sql_auto_is_null, leaving it at 1, so you get the MySQL default, not the SQL standard behavior.

When FLAG_AUTO_IS_NULL is not set, the driver changes the default value of SQL_AUTO_IS_NULL to 0 after connecting, so you get the SQL standard, not the MySQL default behavior.

Thus, omitting the flag disables the compatibility option and forces SQL standard behavior.

See IS NULL. This option was added in Connector/ODBC 3.51.13.

FLAG_ZERO_DATE_TO_MINReturn SQL_NULL_DATA for zero date16777216Translates 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.
FLAG_MIN_DATE_TO_ZEROBind minimal date as zero date33554432Translates 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.
FLAG_MULTI_STATEMENTSAllow multiple statements67108864Enables support for batched statements. This option was added in Connector/ODBC 3.51.18.
FLAG_COLUMN_SIZE_S32Limit column size to 32-bit value134217728Limits 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.
FLAG_NO_BINARY_RESULTAlways handle binary function results as character data268435456When set this option disables charset 63 for columns with an empty org_table. This option was added in Connector/ODBC 3.51.26.
FLAG_DFLT_BIGINT_BIND_STR 536870912Causes BIGINT parameters to be bound as strings. Microsoft Access treats BIGINT as a string on linked tables. The value is read correctly, but bound as a string. This option is used automatically if the driver is used by Microsoft Access.
FLAG_NO_INFORMATION_SCHEMA 1073741824Tells catalog functions not to use INFORMATION_SCHEMA, but rather use legacy algorithms. The trade-off here is usually speed for information quality. Using INFORMATION_SCHEMA is often slow, but the information obtained is more complete.

To select multiple options, add together their values, using the numbers from the Constant Value column in the table.

Замечание

From version of MySQL Connector/ODBC 5.1.6 onwards, you can use the flag name directly as a parameter in the connection string, by specifying the flag name without the FLAG_ prefix. So, in addition to using the options parameter with various flags set, it is now possible to use the flags directly as parameters. For example, FIELD_LENGTH, FOUND_ROWS and DEBUG could all be used as parameters.

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

21.1.4.3. Configuring a Connector/ODBC DSN on Windows

The ODBC Data Source Administrator within Windows lets you 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 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, consider permanently adding 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 21.1.4.3.1, “Configuring a Connector/ODBC 3.51 DSN on Windows”.

To configure a DSN using Connector/ODBC 5.1.1 or later, see Section 21.1.4.3.3, “Configuring a Connector/ODBC 5.1 DSN on Windows”.

21.1.4.3.1. Configuring a Connector/ODBC 3.51 DSN on Windows

To add or configure a Connector/ODBC 3.51 DSN on Windows, use either the command-line, or the ODBC Data Source Administrator GUI.

  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 to access. It can be any valid name that you choose.

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

  6. In the Server field, enter the name of the MySQL server host 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 lets you configure Connector/ODBC connection parameters. Refer to Section 21.1.4.2, “Connector/ODBC Connection Parameters”, for information about the meaning of these options.

Connector/ODBC Connection Advanced
            Dialog
21.1.4.3.2. Configuring a Connector/ODBC 3.51 DSN on Windows, using the command-line

Use myodbc3i.exe when configuring Connector/ODBC 3.51 from the command-line.

Execute myodbc3i.exe without arguments to view a list of available options.

21.1.4.3.3. 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 add or configure a Connector/ODBC 5.1 DSN on Windows, use either the command-line, or the ODBC Data Source Administrator GUI.

  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 to access. It can be any valid name that you choose.

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

  6. In the Server field, enter the name of the MySQL server host 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 where you 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 21.1.4.2, “Connector/ODBC Connection Parameters”.

  • Debug lets you turn on ODBC debugging to record the queries you execute through the DSN to the myodbc.sql file. For more information, see Section 21.1.4.8, “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 lets you configure Connector/ODBC connection parameters. Refer to Section 21.1.4.2, “Connector/ODBC Connection Parameters”, for information about the meaning of these options.

21.1.4.3.4. Configuring a Connector/ODBC 5.1 DSN on Windows, using the command-line

Use myodbc-installer.exe when configuring Connector/ODBC 5.1 or later from the command-line.

Execute myodbc-installer.exe without arguments to view a list of available options.

21.1.4.3.5. Troubleshooting ODBC Connection Problems

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. To debug Connector/ODBC 3.51 (for example, to enable tracing), 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, copy that DLL from a previous version (for example, 3.51.06).

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

To configure a DSN on Mac OS X, you can either use the command-line utility (myodbc3i with connector/OCBC 3.51, or myodbc-installer with connector/ODBC 5.1), edit the odbc.ini file within the Library/ODBC directory of the user, or use the ODBC Administrator GUI. If you have Mac OS X 10.2 or earlier, refer to Section 21.1.4.5, “Configuring a Connector/ODBC DSN on Unix”. Select whether to create a User DSN or a System DSN. When adding a System DSN, you might need to authenticate with the system. Click the padlock and enter a user and password with administrator privileges.

For correct operation of ODBC Administrator, 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 work but not generate 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, use the command-line or edit the odbc.ini file directly. Note that existing DSNs or those that you create using the myodbc3i or myodbc-installer tool 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:

shell> 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 Описание for the DSN.

    ODBC Administrator Add
                DSN Dialog

  5. Click Add to add a new keyword/value pair to the panel. Configure at least four pairs to specify the server, username, password and database connection parameters. See Section 21.1.4.2, “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 other ODBC options in your DSN by adding further keyword/value pairs and setting the corresponding values. See Section 21.1.4.2, “Connector/ODBC Connection Parameters”.

21.1.4.5. 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
Описание  = Connector/ODBC 3.51 Driver DSN
SERVER       = localhost
PORT         =
USER         = root
Password     =
Database     = test
OPTION       = 3
SOCKET       =

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

Refer to the Section 21.1.4.2, “Connector/ODBC Connection Parameters”, for the list of connection parameters that can be supplied.

Замечание

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

21.1.4.6. 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 21.1.4.2, “Connector/ODBC Connection Parameters”, for the list of connection parameters that can be supplied.

21.1.4.7. 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.

21.1.4.8. Getting an ODBC Trace File

If you encounter difficulties or problems with Connector/ODBC, 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.

21.1.4.8.1. Enabling ODBC Tracing on Windows

To enable the trace option on Windows:

  1. The Tracing tab of the ODBC Data Source Administrator dialog box lets you 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.

21.1.4.8.2. Enabling ODBC Tracing on Mac OS X

To enable the trace option on Mac OS X 10.3 or later, 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 check box.

  4. Enter the location to save the Tracing log. To append information to an existing log file, click the Choose... button.

21.1.4.8.3. 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.

21.1.4.8.4. 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 21.1.4.3.5, “Troubleshooting ODBC Connection Problems”.

    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 21.1.8.1, “Connector/ODBC Community Support”.

21.1.5. 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.

21.1.5.1. 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

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

A typical situation where you would install Connector/ODBC is 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 connect to system ALPHA from system BETA with a user name 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 user name 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 user name 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 21.1.4.8, “Getting an ODBC Trace File”, for more information.

21.1.5.3. 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.

21.1.5.4. 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.

21.1.5.4.1. 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 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 to export to. To define a new data source for Connector/ODBC, please Section 21.1.4.3, “Configuring a Connector/ODBC DSN on Windows”.

Замечание

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.

21.1.5.4.2. 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 to import, and then click OK.

21.1.5.4.3. 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 21.1.4.3, “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 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.

21.1.5.5. 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 lets you 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 21.1.4, “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 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 След. 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 След. 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 След. 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.

21.1.5.6. 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.

Замечание

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, follow these steps:

  1. Create a DSN using the Data Sources (ODBC) tool. You can either specify a complete database, including user name and password, or you can build a basic DSN and use Crystal Reports to set the user name 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 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 user name/password combination, or you want to use different authentication credentials, click След. to enter the user name 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 След. 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 След. to continue the process.

    Table links/structure in Crystal
              Reports
  7. You can now select the columns and rows that 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 След. 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.

21.1.5.7. Connector/ODBC Programming

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

This includes, but is 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).

21.1.5.7.1. 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.

21.1.5.7.1.1. 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
21.1.5.7.1.2. 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
21.1.5.7.1.3. 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
21.1.5.7.2. Using Connector/ODBC with .NET

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

21.1.5.7.2.1. 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.Ошибки.Count; i++)
            {
              Console.Write("ERROR #" + i + "\n" +
                            "Message: " +
                            MyOdbcException.Ошибки[i].Message + "\n" +
                            "Native: " +
                            MyOdbcException.Ошибки[i].NativeError.ToString() + "\n" +
                            "Source: " +
                            MyOdbcException.Ошибки[i].Source + "\n" +
                            "SQL: " +
                            MyOdbcException.Ошибки[i].SQLState + "\n");
            }
        }
    }
  }
}
21.1.5.7.2.2. 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

21.1.6. 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.

21.1.6.1. 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.

Замечание

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 enables 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

21.1.6.2. 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

21.1.6.3. 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

21.1.7. 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.

21.1.7.1. 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.

21.1.7.1.1. 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;

This alternative method requires that sql_auto_is_null variable is not set to 0. See Section 5.1.3, “Server System Variables”.

See also Section 21.9.11.3, “How to Get the Unique ID for the Last Inserted Row”.

21.1.7.1.2. 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 check box 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.

21.1.7.1.3. 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 to 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 21.1.4.8, “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.

21.1.7.1.4. 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.

21.1.7.2. 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, 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.

21.1.7.2.1. 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.

21.1.7.2.1.1. Microsoft Access

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

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

  • Include a TIMESTAMP column in all tables that you want to be able to update. For maximum portability, do not use a length specification in the column declaration (which is unsupported within MySQL in versions earlier than 4.1).

  • Include 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 cannot 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:

    Do not use a table data sheet view. Instead, create a form with the fields you want, and use that form data sheet view. Set the DefaultValue property for the TIMESTAMP column to NOW(). Consider hiding the TIMESTAMP column from view so your users are not confused.

  • In some cases, Access may generate SQL statements that MySQL cannot 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, change BLOB columns to TEXT with ALTER TABLE.

  • Access cannot 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:

21.1.7.2.1.2. Microsoft Excel and Column Types

If you have problems importing data into Microsoft Excel, particularly numeric, 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.

21.1.7.2.1.3. Microsoft Visual Basic

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

Visual Basic with ADO cannot 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.

21.1.7.2.1.4. 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.

21.1.7.2.1.5. Visual Objects

Select the Don't optimize column widths option.

21.1.7.2.1.6. 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.

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

Select the Return matching rows option in the DSN.

For more information about how to access MySQL through 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.

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

Some articles that may help with Visual Basic and ASP:

21.1.7.2.2. 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.

21.1.7.2.2.1. 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.

21.1.7.2.2.2. 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('Описание', ' ');
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);
21.1.7.2.2.3. 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.

21.1.7.2.3. 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 lets you use 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 lets you 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:

21.1.7.2.4. Using Connector/ODBC with OpenOffice.org

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

21.1.7.2.5. Using Connector/ODBC with Sambar Server

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

21.1.7.2.6. 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.

21.1.7.2.7. Using Connector/ODBC with SunSystems Vision

Select the Return matching rows option.

21.1.7.3. Connector/ODBC Ошибки 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 21.1.8.1, “Connector/ODBC Community Support”.

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

Questions

  • 22.1.7.3.1: 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.

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

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

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

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

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

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

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

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

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

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

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

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

  • 22.1.7.3.14: 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.

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

  • 22.1.7.3.16: 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.

  • 22.1.7.3.17: When I try to use batched statements, the execution of the batched statements fails.

  • 22.1.7.3.18: 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.

  • 22.1.7.3.19: 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.

  • 22.1.7.3.20: 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.

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

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

  • 22.1.7.3.23: Is it possible to disable data-at-execution using a flag?

  • 22.1.7.3.24: When you call SQLColumns() for a table column that is AUTO_INCREMENT, the NULLABLE column of the result set is always SQL_NULLABLE (1).

Questions and Answers

22.1.7.3.1: 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, 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.

22.1.7.3.2: 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 C.5.2.2, “Can't connect to [local] MySQL server.

22.1.7.3.3: 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.

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.

22.1.7.3.4: 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, 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.

    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, enable the Connector/ODBC Return matching rows option. For Access 2.0, also enable the Simulate ODBC 1.0 option.

  • Include a TIMESTAMP in all tables that you want to be able to update.

  • Include 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 cannot 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.

22.1.7.3.5: 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.

22.1.7.3.6: 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.

22.1.7.3.7: 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.

22.1.7.3.8: 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.

22.1.7.3.9: 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 cannot make sense of a number this big. Select the Change BIGINT columns to INT option (option value 16384).

22.1.7.3.10: 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

22.1.7.3.11: 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 do not help, 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 21.1.4.8, “Getting an ODBC Trace File”.

22.1.7.3.12: 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.

22.1.7.3.13: 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 nonzero (that is, the default value is not 0000-00-00 00:00:00).

22.1.7.3.14: 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.

22.1.7.3.15: 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.

22.1.7.3.16: 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.

22.1.7.3.17: When I try to use batched statements, the execution 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.

22.1.7.3.18: 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.

22.1.7.3.19: 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.

22.1.7.3.20: 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, add the following to your ASP files to ensure that the data returned is correctly encoded:

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

22.1.7.3.21: 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, 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.

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

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

22.1.7.3.23: Is it possible to disable data-at-execution using a flag?

If you do not want to use data-at-execution, simply remove the corresponding calls. For example:

SQLLEN ylen = SQL_LEN_DATA_AT_EXEC(10);
SQLBindCol(hstmt,2,SQL_C_BINARY, buf, 10, &ylen);

Would become:

SQLBindCol(hstmt,2,SQL_C_BINARY, buf, 10, NULL);

Note that in the call to SQLBindCol(), &ylen has been replaced by NULL.

For further information please refer to the MSDN documentation for SQLBindCol().

22.1.7.3.24: When you call SQLColumns() for a table column that is AUTO_INCREMENT, the NULLABLE column of the result set is always SQL_NULLABLE (1).

This is because MySQL reports the DEFAULT value for such a column as NULL. It means, if you insert a NULL value into the column, you will get the next integer value for the table's auto_increment counter.

21.1.8. Connector/ODBC Support

There are many different places where you can get support for using Connector/ODBC. Always try the Connector/ODBC Mailing List or Connector/ODBC Forum. See Section 21.1.8.1, “Connector/ODBC Community Support”, for help before reporting a specific bug or issue to MySQL.

21.1.8.1. Connector/ODBC Community Support

Oracle 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”.

21.1.8.2. How to Report Connector/ODBC Problems or Bugs

If you encounter difficulties or problems with Connector/ODBC, 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 21.1.4.8, “Getting an ODBC Trace File”.

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

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!

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 is 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, 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.

21.1.8.3. 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 .

21.1.8.4. Connector/ODBC Change History

The Connector/ODBC Change History (Changelog) is located with the main Changelog for MySQL. See Section D.2, “MySQL Connector/ODBC (MyODBC) Change History”.

21.1.8.5. 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

21.2. MySQL Connector/Net

Connector/Net lets you easily develop .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:

  • Features provided by MySQL Server up to and including MySQL Server version 5.5.

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

  • Protocol compression, which enables compressing the data stream between the client and server.

  • Connections using TCP/IP sockets, named pipes, or shared memory on Windows.

  • Connections using TCP/IP sockets or Unix sockets on Unix.

  • 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. Синтаксис 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 can also use the MySQL Visual Studio Plugin. The plugin acts as a DDEX (Data Designer Extensibility) provider: you can use the data design tools within Visual Studio to manipulate the schema and objects within a MySQL database. For more information, see Section 21.2.3, “Connector/Net Visual Studio Integration”.

Замечание

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

MySQL Connector/Net supports full versions of Visual Studio 2005, 2008, and 2010, although certain features are only available in Visual Studio 2010 when using MySQL Connector/Net version 6.3.2 and later. Note that MySQL Connector/Net does not currently support Express versions of Microsoft products, including Microsoft Visual Web Developer.

Key topics:

21.2.1. Connector/Net Versions

There are several versions of Connector/Net available:

  • Connector/Net 6.4 includes support for MySQL Server 5.5, 5.1, and 5.0. Important new features include support for Windows authentication (when connecting to MySQL Server 5.5+), table caching on the client side, simple connection fail-over support, and improved SQL generation from the Entity Framework provider.

  • Connector/Net 6.3 includes support for MySQL Server 5.5, 5.1, and 5.0. Important new features include integration with Visual Studio 2010, such as availability of DDL T4 template for Entity Framework, and a custom MySQL SQL Editor. Other features include refactored transaction scope: Connector/Net now supports nested transactions in a scope where they use the same connection string.

  • Connector/Net 6.2 includes support for MySQL Server 5.5, 5.1, 5.0, and 4.1. Important new features include a new logging system and client SSL certificates.

  • Connector/Net 6.1 includes support for MySQL Server 5.5, 5.1, 5.0, and 4.1. Important new features include the MySQL Website Configuration Tool and a Session State Provider.

  • Connector/Net 6.0 includes support for MySQL Server 5.5, 5.1, 5.0, and 4.1.

    This version of Connector/Net is no longer supported.

  • Connector/Net 5.2 includes support for MySQL Server 5.5, 5.1, 5.0, and 4.1 features. Connector/Net 5.2 also includes support for a new membership/role provider, Compact Framework 2.0, a new stored procedure parser and improvements to GetSchema. Connector/Net 5.2 also includes the Visual Studio Plugin as a standard installable component.

    This version of Connector/Net is no longer supported.

  • Connector/Net 5.1 includes support for MySQL Server 5.5, 5.1, 5.0, 4.1, and 4.0 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.

    This version of Connector/Net is no longer supported.

  • Connector/Net 5.0 includes support for MySQL Server 5.1, 5.0, 4.1 and 4.0 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.

    This version of Connector/Net is no longer supported.

  • Connector/Net 1.0 includes support for MySQL Server 5.0, 4.1, and 4.0 features, and full compatibility with the ADO.NET driver interface.

    This version of Connector/Net is no longer supported.

The latest source code for Connector/Net can be downloaded from the MySQL public Subversion server. For further details, see Section 21.2.2.3, “Installing Connector/Net from the source code”.

The following tables shows the .NET Framework version required, and the MySQL Server version supported by Connector/Net:

Table 21.5. Connector/Net Requirements for Related Products

Connector/Net versionADO.NET version supported.NET Framework version requiredMySQL Server version supportedCurrently supported
6.42.x+2.x+, 4.x+ for VS 2010 support5.5, 5.1, 5.0Yes
6.32.x+2.x+, 4.x+ for VS 2010 support5.5, 5.1, 5.0Yes
6.22.x+2.x+5.5, 5.1, 5.0, 4.1Yes
6.12.x+2.x+5.5, 5.1, 5.0, 4.1Yes
6.02.x+2.x+5.5, 5.1, 5.0, 4.1Critical issues only
5.22.x+2.x+5.5, 5.1, 5.0, 4.1No
5.12.x+2.x+5.5, 5.1, 5.0, 4.1, 4.0No
5.02.x+2.x+5.0, 4.1, 4.0No
1.01.x1.x5.0, 4.1, 4.0No
Замечание

Version numbers for MySQL products are formatted as X.Y.Z, where Z=0 indicates alpha, Z=1 indicates beta, and Z>=2 indicates GA. However, Windows tools (Control Panel, properties display) may show the version numbers as XX.YY.ZZ. 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.

21.2.2. 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/5.2.html.

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

21.2.2.1.1. 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 the MSI installer file extracted from the Zip you downloaded. Click След. to start the installation.

    Connector/Net Windows Installer -
              Welcome
  2. You must choose the type of installation to perform.

    Connector/Net Windows Installer -
              Installation type

    For most situations, the Typical installation is 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. 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 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 След. to continue the installation.

    Замечание

    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.

    Connector/Net Windows Installer - Finish
              installation

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: Connector/Net documentation in CHM format.

  • 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 method the user cannot select options. Additionally, no prompts, messages or dialog boxes will be displayed.

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

To provide a progress bar to the user during automatic installation, use the /passive option.

21.2.2.1.2. Installing Connector/Net using the Zip packages

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 file contains the following directories:

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

  • Docs: Connector/Net documentation in CHM format.

  • Samples: Sample code and applications that use the Connector/Net component.

Connector/Net 6.0.x has a different directory structure:

  • Assemblies: A collection of DLLs that make up the connector functionality.

  • Documentation: Connector/Net documentation in CHM format.

  • Samples: sample code and applications that use the Connector/Net component.

There is also another Zip file available for download called mysql-connector-net-version-src.zip. This file contains the source code distribution.

The file contains the following directories:

  • Documentation: Source files to build the documentation into the compiled HTML (CHM) format.

  • Installer: Source files to build the Connector/Net installer program.

  • MySql.Data: Source files for the core data provider.

  • MySql.VisualStudio: Source files for the Microsoft Visual Studio extensions.

  • MySql.Web: Source files for the web providers. This includes code for the membership provider, role provider and profile provider. These are used in ASP.NET web sites.

  • Samples: Source files for several example applications.

  • Tests: A spreadsheet listing test cases.

  • VisualStudio: Resources used by the Visual Studio plugin.

Finally, ensure that MySql.Data.dll is accessible to your program at build time (and run time). If using Microsoft Visual Studio, add MySql.Data as a Reference to your project.

Замечание

If using MySQL Connector/Net 6.3.5 and above, the MySql.Data file provided will work with both .NET Framework 2.x and 4.x.

21.2.2.2. Installing Connector/Net on Unix with Mono

There is no installer available for installing the Connector/Net component on your Unix installation. Before installing, please ensure that you have a working Mono project installation. You can test whether your system has Mono installed by typing:

shell> mono --version

The version of the Mono JIT compiler is displayed.

To compile C# source code, make sure a Mono C# compiler is installed. Note that there are two Mono C# compilers available, mcs, which accesses the 1.0-profile libraries, and gmcs, which accesses the 2.0-profile libraries.

To install Connector/Net on Unix/Mono:

  1. Download the mysql-connector-net-version-noinstall.zip and extract the contents to a directory of your choice, for example: ~/connector-net/.

  2. In the directory where you unzipped the connector to, change into the bin directory. Ensure the file MySql.Data.dll is present.

  3. You must register the Connector/Net component, MySql.Data, in the Global Assembly Cache (GAC). In the current directory enter the gacutil command:

    root-shell> gacutil /i MySql.Data.dll

    This will register MySql.Data into the GAC. You can check this by listing the contents of /usr/lib/mono/gac, where you will find MySql.Data if the registration has been successful.

You are now ready to compile your application. You must ensure that when you compile your application you include the Connector/Net component using the -r: command-line option. For example:

shell> gmcs -r:System.dll -r:System.Data.dll -r:MySql.Data.dll HelloWorld.cs

Note, the assemblies that are referenced depend on the requirements of the application, but applications using Connector/Net must provide -r:MySql.Data as a minimum.

You can further check your installation by running the compiled program, for example:

shell> mono HelloWorld.exe

21.2.2.3. Installing Connector/Net from the source code

Caution

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, use a standard release distribution.

Obtaining the source code

To obtain the most recent development source tree, you first need to download and install Bazaar. You can obtain Bazaar from the Bazaar VCS Website. Bazaar is supported by any platform that supports Python, and is therefore compatible with any Linux, Unix, Windows or Mac OS X host. Instructions for downloading and installing Bazaar on the different platforms are available on the Bazaar Web site.

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

To check out 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> bzr branch lp:connectornet/trunk

To download a specific version of Connector/Net, specify the version number instead of trunk. For example, to obtain a copy of the 6.0 version of the source tree:

shell> bzr branch lp:connectornet/6.0

Source packages are also available on the downloads page.

Building the source code on Windows

The following procedure can be used to build the connector on Microsoft Windows.

  • Obtain the source code, either from the Subversion server, or through one of the prepared source code packages.

  • Navigate to the root of the source code tree.

  • A Microsoft Visual Studio 2005 solution file is available to build the connector, this is called MySQL-VS2005.sln. Click this file to load the solution into Visual Studio.

  • Select Build, Build Solution from the main menu to build the solution.

Building the source code on Unix

Support for building Connector/Net on Mono/Unix is currently not available.

21.2.3. Connector/Net Visual Studio Integration

When MySQL Connector/Net is installed on Microsoft Windows, Visual Studio integration components are also installed and initialized. This enables the developer to work seamlessly with MySQL Connector/Net in the familiar Visual Studio environment, as described in the following sections of the manual.

MySQL Connector/Net supports Visual Studio versions 2005, 2008, and 2010. However, only MySQL Connector/Net version 6.3 fully integrates with Visual Studio 2010, although applications using earlier versions of the connector can be built with the Visual Studio 2010 environment using .NET 2.x frameworks.

Visual Studio 2010 support was introduced with MySQL Connector/Net 6.3.2. From version 6.3.2 the connector ships with both .NET 2.x and .NET 4.x versions of the entity framework support files, mysql.data.ef.dll and mysql.visualstudio.dll. The .NET 4.x versions need to be shipped to enable new integration features supported in Visual Studio 2010, including:

  • New DDL T4 template for the Entity Framework (EF) - This enables developers to design an EF model from scratch and use the native Visual Studio 2010 facility to generate MySQL DDL from that model. This is done by creating the model, and with the model open, choosing the SSDLToMySQL template in the properties window. The correct DDL is then generated. The developer can then save this code as a .mysql file in their project and execute it against the MySQL server.

  • New SQL Editor - A new SQL editor has been included that enables connections to servers to execute SQL. This is activated by creating a new file with a .mysql extension. A new template is also included to allow creation of this file type using the Visual Studio 2010 main menu item File, New. Note that the MySQL SQL Editor is also available in 2005 and 2008.

21.2.3.1. Making a connection

Once the connector 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:

  • Start Visual Studio, and open the Server Explorer window (View, Server Explorer option in the main Visual Studio menu, or Control+W, L keyboard shortcuts).

  • Right-click the Data Connections node, and choose the Add Connection... menu item.

  • Add Connection dialog opens. Press the Change button to choose MySQL Database as a data source.

    Figure 21.1. Add Connection Context Menu

    Add Connection Context Menu

  • Change Data Source dialog opens. 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.

    Figure 21.2. Choose Data Source

    Choose Data Source

  • Input 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 schema name. Note that you must specify the default schema name to open the connection.

    Figure 21.3. Add Connection Dialog

    Add Connection Dialog

  • You can also set the port to connect with the MySQL server by pressing the Advanced button. To test connection with the MySQL server, set the server host name, the user name, and the password, and press the Test Connection button. If the test succeeds, the success confirmation dialog opens.

  • 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 GUI.

    Figure 21.4. New Data Connection

    New Data Connection

After the connection is successfully established, all settings are saved for future use. When you start Visual Studio for the next time, just open the connection node in Server Explorer to establish a connection to the MySQL server again.

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 the connection may be modified or deleted only if no active editor for its objects is opened: otherwise you may loose your data.

21.2.3.2. Editing Tables

Connector/Net contains a table editor, which enables the visual creation and modification of tables.

The Table Designer can be accessed through a mouse action on table-type node of Server Explorer. To create a new table, right-click the Tables node (under the connection node) and choose the Create Table command from the context menu.

To modify an existing table, double-click the node of the table to modify, or right-click this node and choose the Design item from the context menu. Either of the commands opens the Table Designer.

The table editor is implemented in the manner of the well-known Query Browser Table Editor, but with minor differences.

Figure 21.5. Editing New Table

Editing New Table

Table Designer consists of the following parts:

  • Columns Editor - a data grid on top of the Table Designer. Use the Columns grid for column creation, modification, and deletion.

  • Indexes tab - a tab on bottom of the Table Designer. Use the Indexes tab for indexes management.

  • Foreign Keys tab - a tab on bottom of the Table Designer. Use the Foreign Keys tab for foreign keys management.

  • Column Details tab - a tab on bottom of the Table Designer. Use the Column Details tab to set advanced column options.

  • Properties window - a standard Visual Studio Properties window, where the properties of the edited table are displayed. Use the Properties window to set the table properties.

Each of these areas is discussed in more detail in subsequent sections.

To save changes you have made in the Table Designer, use either Save or Save All button of the Visual Studio main toolbar, or just press Control+S. If you have not already named the table you will be prompted to do so.

Figure 21.6. Choose Table Name

Choose Table Name

Once created you can view the table in the Server Explorer.

Figure 21.7. Newly Created Table

Newly Created Table

The Table Designer main menu enables you to set a Primary Key column, edit Relationships such as Foreign Keys, and create Indexes.

Figure 21.8. Table Designer Main Menu

Table Designer Main Menu
21.2.3.2.1. 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 focus to a needed cell of a grid, use the mouse click. Also 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, activate the appropriate cell and type the desired value.

To set or unset flag-type column properties (NOT NULL, auto incremented, flags), check or uncheck the corresponding check boxes. Note that the set of column flags depends on its data type.

To reorder columns, index columns or foreign key columns in the Column Editor, select the whole column to reorder by clicking the selector column on the left of the column grid. Then move the column by using Control+Up (to move the column up) or Control+Down (to move the column down) keys.

To delete a column, select it by clicking the selector column on the left of the column grid, then press the Delete button on a keyboard.

21.2.3.2.2. Editing Indexes

Indexes management is performed using the Indexes/Keys dialog.

To add an index, select Table Designer, Indexes/Keys... from the main menu, and click Add to add a new index. You can then set the index name, index kind, index type, and a set of index columns.

Figure 21.9. Indexes Dialog

Indexes Dialog

To remove an index, select it in the list box on the left, and click the Delete button.

To change index settings, select the needed index in the list box on the left. The detailed information about the index is displayed in the panel on the right hand side. Change the desired values.

21.2.3.2.3. Editing Foreign Keys

Foreign Keys management is performed using the Foreign Key Relationships dialog.

To add a foreign key, select Table Designer, Relationships... from the main menu. This displays the Foreign Key Relationship dialog. Click Add. You can then set the foreign key name, referenced table name, foreign key columns, and actions upon update and delete.

To remove a foreign key, select it in the list box on the left, and click the Delete button.

To change foreign key settings, select the required foreign key in the list box on the left. The detailed information about the foreign key is displayed in the right hand panel. Change the desired values.

Figure 21.10. Foreign Key Relationships Dialog

Foreign Key Relationships Dialog
21.2.3.2.4. Column Properties

The Column Properties tab can be used to set column options. In addition to the general column properties presented in the Column Editor, in the Column Properties tab you can set additional properties such as Character Set, Collation and Precision.

21.2.3.2.5. Table Properties

To bring up Table Properties select the table and right-click to activate the context menu. Select Properties. The Table Properties dockable window will be displayed.

Figure 21.11. Table Properties Menu Item

Table Properties Menu Item

The following table properties can be set:

  • Auto Increment

  • Average Row Length

  • Character Set

  • Collation

  • Comment

  • Data Directory

  • Index Directory

  • Maximum Rows

  • Minimum Rows

  • Name

  • Row Format

  • Schema

  • Storage Engine

The property Schema is read only.

Figure 21.12. Table Properties

Table Properties

21.2.3.3. Editing Views

To create a new view, right-click the Views node under the connection node in Server Explorer. From the node's context menu, choose the Create View command. This command opens the SQL Editor.

Figure 21.13. Editing View SQL

Editing View SQL

You can then enter the SQL for your view.

Figure 21.14. View SQL Added

View SQL Added

To modify an existing view, double-click a node of the view to modify, or right-click this node and choose the Alter View command from a context menu. Either of the commands opens the SQL Editor.

All other view properties can be set in the Properties window. These properties are:

  • Catalog

  • Check Option

  • Definer

  • Definition

  • Definer

  • Is Updateable

  • Name

  • Schema

  • Security Type

Some of these properties can have arbitrary text values, others accept values from a predefined set. In the latter case you set the desired value with an embedded combobox.

The properties Is Updatable and Schema are readonly.

To save changes you have made, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Control+S.

Figure 21.15. View SQL Saved

View SQL Saved

21.2.3.4. 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 node's context menu, choose the Create Routine command. This command opens the SQL Editor.

Figure 21.16. Edit Stored Procedure SQL

Edit Stored Procedure SQL

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 the node of the routine to modify, or right-click this node and choose the Alter Routine command from the 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:

  • Body

  • Catalog

  • Comment

  • Creation Time

  • Data Access

  • Definer

  • Definition

  • External Name

  • External Language

  • Is Deterministic

  • Last Modified

  • Name

  • Parameter Style

  • Returns

  • Schema

  • Security Type

  • Specific Name

  • SQL Mode

  • SQL Path

  • Type

Some of these properties can have arbitrary text values, others accept values from a predefined set. In the latter case set the desired value using the embedded combo box.

You can also 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.

To save changes you have made, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Control+S.

Figure 21.17. Stored Procedure SQL Saved

Stored Procedure SQL Saved

21.2.3.5. Editing Triggers

To create a new trigger, right-click the node of the table in which to add the 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 the node of the trigger to modify, or right-click this node and choose the Alter Trigger command from the 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.

Замечание

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 from a predefined set. In the latter case set the desired value using the embedded combo box.

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 Control+S. Before changes are saved, you will be asked to confirm the execution of the corresponding SQL query in a confirmation dialog.

21.2.3.6. 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 the node of the UDF to modify, or right-click this node and choose the Alter UDF command from the context menu. Either of these commands opens the UDF Editor.

The UDF editor enables you to set the following properties:

  • Name

  • So-name (DLL name)

  • Return type

  • Is Aggregate

There are text fields for both names, a combo box for the return type, and a check box to indicate if the UDF is aggregate. All these options are also accessible using the Properties window.

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 Control+S. Before changes are saved, you will be asked to confirm the execution of the corresponding SQL query in a confirmation dialog.

21.2.3.7. Cloning Database Objects

Tables, views, stored procedures, and functions can be cloned using the appropriate Clone command from the 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.

The editor is filled with values of the original object. You can modify these values in a usual manner.

To save the cloned object, use either Save or Save All buttons of the Visual Studio main toolbar, or just press Control+S. Before changes are saved, you will be asked to confirm the execution of the corresponding SQL query in a confirmation dialog.

21.2.3.8. Dropping Database Objects

Tables, views, stored routines, triggers, and UDFs can be dropped with the appropriate Drop command selected 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.

21.2.3.9. Using the ADO.NET Entity Framework

Connector/Net 6.0 introduced support for the ADO.NET Entity Framework. ADO.NET Entity Framework was included with .NET Framework 3.5 Service Pack 1, and Visual Studio 2008 Service Pack 1. ADO.NET Entity Framework was released on 11th August 2008.

ADO.NET Entity Framework provides an Object Relational Mapping (ORM) service, mapping the relational database schema to objects. The ADO.NET Entity Framework defines several layers, these can be summarized as:

  • Logical - this layer defines the relational data and is defined by the Store Schema Definition Language (SSDL).

  • Conceptual - this layer defines the .NET classes and is defined by the Conceptual Schema Definition Language (CSDL)

  • Mapping - this layer defines the mapping from .NET classes to relational tables and associations, and is defined by Mapping Specification Language (MSL).

Connector/Net integrates with Visual Studio 2008 to provide a range of helpful tools to assist the developer.

A full treatment of ADO.NET Entity Framework is beyond the scope of this manual. You are encouraged to review the Microsoft ADO.NET Entity Framework documentation.

Tutorials on getting started with ADO.NET Entity Framework are available. See Section 21.2.4.5, “Tutorial: Using an Entity Framework Entity as a Windows Forms Data Source” and Section 21.2.4.6, “Tutorial: Databinding in ASP.NET using LINQ on Entities”.

21.2.3.10. MySQL Website Configuration Tool

MySQL Connector/Net 6.1 introduced the MySQL Website Configuration Tool. This is a facility available in Visual Studio that enables you to configure the Membership, Role, Session State and Profile Provider, without having to resort to editing configuration files. You simply run the tool, set your configuration options, and the tool will modify your web.config file accordingly.

The MySQL Website Configuration Tool appears as a small icon on the Solution Explorer toolbar in Visual Studio, as show by the following screenshot:

Figure 21.18. MySQL Website Configuration Tool

MySQL Website Configuration Tool

Clicking the Website Configuration Tool icon launches the wizard and displays the first screen:

Figure 21.19. MySQL Website Configuration Tool - Membership

MySQL Website Configuration Tool -
          Membership

This allows you to enable use of the MySQL Membership Provider. Simply click the check box to enable this. You can now enter the name of the application that you are creating the configuration for. You can also enter a description for the application.

You can then click the Edit... button to launch the Connection String Editor:

Figure 21.20. MySQL Website Configuration Tool - Connection String Editor

MySQL Website Configuration Tool -
          Connection String Editor

Note that if you have already defined a connection string for the providers manually in web.config, or previously using the tool, this will be automatically loaded and displayed, and can then be modified in this dialog.

You can also ensure that the necessary schema are created automatically for you by selecting the Autogenerate Schema check box. These schema are used to store membership information. The database used to storage is the one specified in the connection string.

You can also ensure that exceptions generated by the application will be written to the event log by selecting the Write exceptions to event log check box.

Clicking the Advanced... button launches a dialog that enables you to set Membership Options. These options dictate such variables as password length required when a user signs up, whether the password is encrypted and whether the user can reset their password or not.

Figure 21.21. MySQL Website Configuration Tool - Advanced Options

MySQL Website Configuration Tool - Advanced
          Options

Once information has been set up as required for configuration of the Membership Provider the След. button can be clicked to display the Roles Provider screen:

Figure 21.22. MySQL Website Configuration Tool - Roles

MySQL Website Configuration Tool -
          Roles

Again the connection string can be edited, a description added and Autogenerate Schema can be enabled before clicking След. to go to the Profiles Provider screen:

Figure 21.23. MySQL Website Configuration Tool - Profiles

MySQL Website Configuration Tool -
          Profiles

This screen display similar options to the previous screens.

Click След. to proceed to the Session State configuration page:

Figure 21.24. MySQL Website Configuration Tool - Session State

MySQL Website Configuration Tool - Session
          State

Once you have set up the Session State Provider as required, click Finish to exit the wizard.

At this point it is necessary to select the Authentication Type to From Internet. This can be done by launching the ASP.NET Configuration Tool, and selecting the Security tab. Click the Select authentication type link and ensure that the From the internet radio button is selected. You can now examine the database you created to store membership information. All the necessary tables will have been created for you:

Figure 21.25. MySQL Website Configuration Tool - Tables

MySQL Website Configuration Tool -
          Tables

21.2.3.11. MySQL SQL Editor

MySQL Connector/Net 6.3.2 introduced a new MySQL SQL Editor. The easiest way to invoke the editor is by selecting the New, File menu item from the Visual Studio main menu. This displays the New File dialog:

Figure 21.26. MySQL SQL Editor - New File

MySQL SQL Editor - New File

From the New File dialog select the MySQL template, and then double-click the MySQL SQL Script document, or click the Open button.

The MySQL SQL Editor will be displayed. You can now enter SQL code as required, or connect to a MySQL server. Click the Connect to MySQL button in the MySQL SQL Editor toolbar. You can enter the connection details into the Connect to MySQL dialog that is displayed. You can enter the server name, user id, password and database to connect to, or click the Advanced button to select other connection string options. Click the Connect button to connect to the MySQL server. It is now possible to execute your SQL code against the server by clicking the Run SQL button on the toolbar.

Figure 21.27. MySQL SQL Editor - Query

MySQL SQL Editor - Query

The results from any queries are displayed on the Results tab. Any errors are displayed on the Messages tab.

21.2.3.12. DDL T4 Template Macro

MySQL Connector/Net 6.3 introduced the ability to convert an Entity Framework model to MySQL DDL code. Starting with a blank model, an entity model can be developed in Visual Studio's designer. Once the model has been created, the model's properties can be selected, and in the Database Script Generation category of the model's properties, the property DDL Generation can be found. The value SSDLToMySQL.tt(VS) can then be selected from the drop-down listbox.

Figure 21.28. DDL T4 Template Macro - Model Properties

DDL T4 Template Macro - Model
          Properties

Right-clicking the model design area will display a context-sensitive menu. Selecting Generate Database from Model from the menu will display the Generate Database Wizard. The wizard can then be used to generate MySQL DDL code.

Figure 21.29. DDL T4 Template Macro - Generate Database Wizard

DDL T4 Template Macro - Generate Database
          Wizard

21.2.4. Connector/Net Tutorials

21.2.4.1. Tutorial: An Introduction to Connector/Net Programming

This section provides a gentle introduction to programming with Connector/Net. The example code is written in C#, and is designed to work on both Microsoft .NET Framework and Mono.

This tutorial is designed to get you up and running with Connector/Net as quickly as possible, it does not go into detail on any particular topic. However, the following sections of this manual describe each of the topics introduced in this tutorial in more detail. In this tutorial you are encouraged to type in and run the code, modifying it as required for your setup.

This tutorial assumes you have MySQL and Connector/Net already installed. It also assumes that you have installed the World example database, which can be downloaded from the MySQL Documentation page. You can also find details on how to install the database on the same page.

Замечание

Before compiling the example code make sure that you have added References to your project as required. The References required are System, System.Data and MySql.Data.

21.2.4.1.1. The MySqlConnection Object

For your Connector/Net application to connect to a MySQL database it needs to establish a connection. This is achieved through the use of a MySqlConnection object.

The MySqlConnection constructor takes a connection string as one of its parameters. The connection string provides necessary information to make the connection to the MySQL database. The connection string is discussed more fully in Section 21.2.5.1, “Connecting to MySQL Using Connector/Net”. A reference containing a list of supported connection string options can also be found in Section 21.2.6, “Connector/Net Connection String Options Reference”.

The following code shows how to create a connection object.

using System;
using System.Data;

using MySql.Data;
using MySql.Data.MySqlClient;

public class Tutorial1
{
    public static void Main()
    {
        string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
        MySqlConnection conn = new MySqlConnection(connStr);
        try
        {
            Console.WriteLine("Connecting to MySQL...");
            conn.Open();
            // Perform database operations
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }
        conn.Close();
        Console.WriteLine("Done.");
    }
}

When the MySqlConnection constructor is invoked it returns a connection object, which is used for subsequent database operations. The first operation in this example is to open the connection. This needs to be done before further operations take place. Before the application exits the connection to the database needs to be closed by calling Close on the connection object.

Sometimes an attempt to perform an Open on a connection object can fail, this will generate an exception that can be handled using standard exception handling code.

In this section you have learned how to create a connection to a MySQL database, and open and close the corresponding connection object.

21.2.4.1.2. The MySqlCommand Object

Once a connection has been established with the MySQL database, the next step is do carry out the desired database operations. This can be achieved through the use of the MySqlCommand object.

You will see how to create a MySqlCommand object. Once it has been created there are three main methods of interest that you can call:

  • ExecuteReader - used to query the database. Results are usually returned in a MySqlDataReader object, created by ExecuteReader.

  • ExecuteNonQuery - used to insert and delete data.

  • ExecuteScalar - used to return a single value.

Once a MySqlCommand object has been created, you will call one of the above methods on it to carry out a database operation, such as perform a query. The results are usually returned into a MySqlDataReader object, and then processed, for example the results might be displayed. The following code demonstrates how this could be done.

using System;
using System.Data;

using MySql.Data;
using MySql.Data.MySqlClient;

public class Tutorial2
{
    public static void Main()
    {
        string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
        MySqlConnection conn = new MySqlConnection(connStr);
        try
        {
            Console.WriteLine("Connecting to MySQL...");
            conn.Open();

            string sql = "SELECT Name, HeadOfState FROM Country WHERE Continent='Oceania'";
            MySqlCommand cmd = new MySqlCommand(sql, conn);
            MySqlDataReader rdr = cmd.ExecuteReader();

            while (rdr.Read())
            {
                Console.WriteLine(rdr[0]+" -- "+rdr[1]);
            }
            rdr.Close();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }

        conn.Close();
        Console.WriteLine("Done.");
    }
}

When a connection has been created and opened, the code then creates a MySqlCommand object. Note that the SQL query to be executed is passed to the MySqlCommand constructor. The ExecuteReader method is then used to generate a MySqlReader object. The MySqlReader object contains the results generated by the SQL executed on the command object. Once the results have been obtained in a MySqlReader object, the results can be processed. In this case the information is simply printed out as part of a while loop. Finally, the MySqlReader object is disposed of by running its Close method on it.

In the next example you will see how to use the ExecuteNonQuery method.

The procedure for performing an ExecuteNonQuery method call is simpler, as there is no need to create an object to store results. This is because ExecuteNonQuery is only used for inserting, updating and deleting data. The following example illustrates a simple update to the Country table:

using System;
using System.Data;

using MySql.Data;
using MySql.Data.MySqlClient;

public class Tutorial3
{
    public static void Main()
    {
        string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
        MySqlConnection conn = new MySqlConnection(connStr);
        try
        {
            Console.WriteLine("Connecting to MySQL...");
            conn.Open();

            string sql = "INSERT INTO Country (Name, HeadOfState, Continent) VALUES ('Disneyland','Mickey Mouse', 'North America')";
            MySqlCommand cmd = new MySqlCommand(sql, conn);
            cmd.ExecuteNonQuery();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }

        conn.Close();
        Console.WriteLine("Done.");
    }
}

The query is constructed, the command object created and the ExecuteNonQuery method called on the command object. You can access your MySQL database with the MySQL Client program and verify that the update was carried out correctly.

Finally, you will see how the ExecuteScalar method can be used to return a single value. Again, this is straightforward, as a MySqlDataReader object is not required to store results, a simple variable will do. The following code illustrates how to use ExecuteScalar:

using System;
using System.Data;

using MySql.Data;
using MySql.Data.MySqlClient;

public class Tutorial4
{
    public static void Main()
    {
        string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
        MySqlConnection conn = new MySqlConnection(connStr);
        try
        {
            Console.WriteLine("Connecting to MySQL...");
            conn.Open();

            string sql = "SELECT COUNT(*) FROM Country";
            MySqlCommand cmd = new MySqlCommand(sql, conn);
            object result = cmd.ExecuteScalar();
            if (result != null)
            {
                int r = Convert.ToInt32(result);
                Console.WriteLine("Number of countries in the World database is: " + r);
            }

        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }

        conn.Close();
        Console.WriteLine("Done.");
    }
}

This example uses a simple query to count the rows in the Country table. The result is obtained by calling ExecuteScalar on the command object.

21.2.4.1.3. Working with Decoupled Data

Previously, when using MySqlDataReader, the connection to the database was continually maintained, unless explicitly closed. It is also possible to work in a manner where a connection is only established when needed. For example, in this mode, a connection could be established to read a chunk of data, the data could then be modified by the application as required. A connection could then be reestablished only if and when the application needs to write data back to the database. This decouples the working data set from the database.

This decouple mode of working with data is supported by Connector/Net. There are several parts involved in allowing this method to work:

  • Data Set - The Data Set is the area in which data is loaded to read or modify it. A DataSet object is instantiated, which can store multiple tables of data.

  • Data Adapter - The Data Adapter is the interface between the Data Set and the database itself. The Data Adapter is responsible for efficiently managing connections to the database, opening and closing them as required. The Data Adapter is created by instantiating an object of the MySqlDataAdapter class. The MySqlDataAdapter object has two main methods: Fill which reads data into the Data Set, and Update, which writes data from the Data Set to the database.

  • Command Builder - The Command Builder is a support object. The Command Builder works in conjunction with the Data Adapter. When a MySqlDataAdapter object is created, it is typically given an initial SELECT statement. From this SELECT statement the Command Builder can work out the corresponding INSERT, UPDATE and DELETE statements that would be required to update the database. To create the Command Builder, an object of the class MySqlCommandBuilder is created.

Each of these classes will now be discussed in more detail.

Instantiating a DataSet object

A DataSet object can be created simply, as shown in the following example code snippet:

DataSet dsCountry;
...
dsCountry = new DataSet();

Although this creates the DataSet object it has not yet filled it with data. For that a Data Adapter is required.

Instantiating a MySqlDataAdapter object

The MySqlDataAdapter can be created as illustrated by the following example:

MySqlDataAdapter daCountry;
...
string sql = "SELECT Code, Name, HeadOfState FROM Country WHERE Continent='North America'";
daCountry = new MySqlDataAdapter (sql, conn);

Note, the MySqlDataAdapter is given the SQL specifying the data to work with.

Instantiating a MySqlCommandBuilder object

Once the MySqlDataAdapter has been created, it is necessary to generate the additional statements required for inserting, updating and deleting data. There are several ways to do this, but in this tutorial you will see how this can most easily be done with MySqlCommandBuilder. The following code snippet illustrates how this is done:

MySqlCommandBuilder cb = new MySqlCommandBuilder(daCountry);

Note that the MySqlDataAdapter object is passed as a parameter to the command builder.

Filling the Data Set

To do anything useful with the data from your database, you need to load it into a Data Set. This is one of the jobs of the MySqlDataAdapter object, and is carried out with its Fill method. The following example code illustrates this:

DataSet dsCountry;
...
dsCountry = new DataSet();
...
daCountry.Fill(dsCountry, "Country");

Note the Fill method is a MySqlDataAdapter method, the Data Adapter knows how to establish a connec tion with the database and retrieve the required data, and then populates the Data Set when the Fill method is called. The second parameter “Country” is the table in the Data Set to update.

Updating the Data Set

The data in the Data Set can now be manipulated by the application as required. At some point, changes to data will need to be written back to the database. This is achieved through a MySqlDataAdapter method, the Update method.

daCountry.Update(dsCountry, "Country");

Again, the Data Set and the table within the Data Set to update are specified.

Working Пример

The interactions between the DataSet, MySqlDataAdapter and MySqlCommandBuilder classes can be a little confusing, so their operation can perhaps be best illustrated by working code.

In this example, data from the World database is read into a Data Grid View control. Here, the data can be viewed and changed before clicking an update button. The update button then activates code to write changes back to the database. The code uses the principles explained above. The application was built using the Microsoft Visual Studio to place and create the user interface controls, but the main code that uses the key classes described above is shown below, and is portable.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

using MySql.Data;
using MySql.Data.MySqlClient;

namespace WindowsFormsApplication5
{
    public partial class Form1 : Form
    {
        MySqlDataAdapter daCountry;
        DataSet dsCountry;

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

            string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
            MySqlConnection conn = new MySqlConnection(connStr);
            try
            {
                label2.Text = "Connecting to MySQL...";

                string sql = "SELECT Code, Name, HeadOfState FROM Country WHERE Continent='North America'";
                daCountry = new MySqlDataAdapter (sql, conn);
                MySqlCommandBuilder cb = new MySqlCommandBuilder(daCountry);

                dsCountry = new DataSet();
                daCountry.Fill(dsCountry, "Country");
                dataGridView1.DataSource = dsCountry;
                dataGridView1.DataMember = "Country";
            }
            catch (Exception ex)
            {
                label2.Text = ex.ToString();
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            daCountry.Update(dsCountry, "Country");
            label2.Text = "MySQL Database Updated!";
        }

    }
}

The application running is shown below:

Figure 21.30. World Database Application

World Database Application
21.2.4.1.4. Working with Parameters

This part of the tutorial shows you how to use parameters in your Connector/Net application.

Although it is possible to build SQL query strings directly from user input, this is not advisable as it does not prevent erroneous or malicious information being entered. It is safer to use parameters as they will be processed as field data only. For example, imagine the following query was constructed from user input:

string sql = "SELECT Name, HeadOfState FROM Country WHERE Continent = "+user_continent;

If the string user_continent came from a Text Box control, there would potentially be no control over the string entered by the user. The user could enter a string that generates a run time error, or in the worst case actually harms the system. When using parameters it is not possible to do this because a parameter is only ever treated as a field parameter, rather than an arbitrary piece of SQL code.

The same query written user a parameter for user input would be:

string sql = "SELECT Name, HeadOfState FROM Country WHERE Continent = @Continent";

Note that the parameter is preceded by an '@' symbol to indicate it is to be treated as a parameter.

As well as marking the position of the parameter in the query string, it is necessary to add a parameter to the Command object. This is illustrated by the following code snippet:

cmd.Parameters.AddWithValue("@Continent", "North America");

In this example the string "North America" is supplied as the parameter value statically, but in a more practical example it would come from a user input control.

A further example illustrates the complete process:

using System;
using System.Data;

using MySql.Data;
using MySql.Data.MySqlClient;

public class Tutorial5
{
    public static void Main()
    {
        string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
        MySqlConnection conn = new MySqlConnection(connStr);
        try
        {
            Console.WriteLine("Connecting to MySQL...");
            conn.Open();

            string sql = "SELECT Name, HeadOfState FROM Country WHERE Continent=@Continent";
            MySqlCommand cmd = new MySqlCommand(sql, conn);

            Console.WriteLine("Enter a continent e.g. 'North America', 'Europe': ");
            string user_input = Console.ReadLine();

            cmd.Parameters.AddWithValue("@Continent", user_input);

            MySqlDataReader rdr = cmd.ExecuteReader();

            while (rdr.Read())
            {
                Console.WriteLine(rdr["Name"]+" --- "+rdr["HeadOfState"]);
            }
            rdr.Close();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }

        conn.Close();
        Console.WriteLine("Done.");
    }
}

In this part of the tutorial you have see how to use parameters to make your code more secure.

21.2.4.1.5. Working with Stored Procedures

In this section you will see how to work with Stored Procedures. This section assumes you have a basic understanding of what a Stored Procedure is, and how to create one.

For the purposes of this tutorial, you will create a simple Stored Procedure to see how it can be called from Connector/Net. In the MySQL Client program, connect to the World database and enter the following Stored Procedure:

DELIMITER //
CREATE PROCEDURE country_hos
(IN con CHAR(20))
BEGIN
  SELECT Name, HeadOfState FROM Country
  WHERE Continent = con;
END //
DELIMITER ;

Test the Stored Procedure works as expected by typing the following into the MySQL Client program:

CALL country_hos('Europe');

Note that The Stored Routine takes a single parameter, which is the continent to restrict your search to.

Having confirmed that the Stored Procedure is present and correct you can now move on to seeing how it can be accessed from Connector/Net.

Calling a Stored Procedure from your Connector/Net application is similar to techniques you have seen earlier in this tutorial. A MySqlCommand object is created, but rather than taking an SQL query as a parameter it takes the name of the Stored Procedure to call. The MySqlCommand object also needs to be set to the type of Stored Procedure. This is illustrated by the following code snippet:

string rtn = "country_hos";
MySqlCommand cmd = new MySqlCommand(rtn, conn);
cmd.CommandType = CommandType.StoredProcedure;

In this case you also need to pass a parameter to the Stored Procedure. This can be achieved using the techniques seen in the previous section on parameters, Section 21.2.4.1.4, “Working with Parameters”. This is shown in the following code snippet:

cmd.Parameters.AddWithValue("@con", "Europe");

The value of the parameter @con could more realistically have come from a user input control, but for simplicity it is set as a static string in this example.

At this point everything is set up and all that now needs to be done is to call the routine. This can be achieved using techniques also learned in earlier sections, but in this case the ExecuteReader method of the MySqlCommand object is used.

Complete working code for the Stored Procedure example is shown below:

using System;
using System.Data;

using MySql.Data;
using MySql.Data.MySqlClient;

public class Tutorial6
{
    public static void Main()
    {
        string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
        MySqlConnection conn = new MySqlConnection(connStr);
        try
        {
            Console.WriteLine("Connecting to MySQL...");
            conn.Open();

            string rtn = "country_hos";
            MySqlCommand cmd = new MySqlCommand(rtn, conn);
            cmd.CommandType = CommandType.StoredProcedure;

            cmd.Parameters.AddWithValue("@con", "Europe");

            MySqlDataReader rdr = cmd.ExecuteReader();
            while (rdr.Read())
            {
                Console.WriteLine(rdr[0] + " --- " + rdr[1]);
            }
            rdr.Close();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }

        conn.Close();
        Console.WriteLine("Done.");
    }
}

In this section you have seen how to call a Stored Procedure from Connector/Net. For the moment, this concludes our introductory tutorial on programming with Connector/Net.

21.2.4.2. Tutorial: MySQL Connector/Net ASP.NET Membership and Role Provider

Many web sites feature the facility for the user to create a user account. They can then log into the web site and enjoy a personalized experience. This requires that the developer creates database tables to store user information, along with code to gather and process this data. This represents a burden on the developer, and there is the possibility for security issues to creep into the developed code. However, ASP.NET 2.0 introduced the Membership system. This system is designed around the concept of Membership, Profile and Role Providers, which together provide all of the functionality to implement a user system, that previously would have to have been created by the developer from scratch.

Currently, MySQL Connector/Net provides Membership, Role, Profile and Session State Providers.

This tutorial shows you how to set up your ASP.NET web application to use the MySQL Connector/Net Membership and Role Providers. It assumes that you have MySQL Server installed, along with MySQL Connector/Net and Microsoft Visual Studio. This tutorial was tested with MySQL Connector/Net 6.0.4 and Microsoft Visual Studio 2008 Professional Edition. It is recommended you use 6.0.4 or above for this tutorial.

  1. Create a new database in the MySQL Server using the MySQL Command Line Client program (mysql), or other suitable tool. It does not matter what name is used for the database, but record it. You specify it in the connection string constructed later in this tutorial. This database contains the tables, automatically created for you later, used to store data about users and roles.

  2. Create a new ASP.NET Web Site in Visual Studio. If you are not sure how to do this, refer to the following tutorial: Section 21.2.4.6, “Tutorial: Databinding in ASP.NET using LINQ on Entities”, which demonstrates how to create a simple ASP.NET web site.

  3. Add References to MySql.Data and MySql.Web to the web site project.

  4. Locate the machine.config file on your system, which is the configuration file for the .NET Framework.

  5. Search the machine.config file to find the membership provider MySQLMembershipProvider.

  6. Add the attribute autogenerateschema="true". The appropriate section should now resemble the following (note: for the sake of brevity some information has been excluded):

    <membership>
     <providers>
       <add name="AspNetSqlMembershipProvider" 
         type="System.Web.Security.SqlMembershipProvider" 
         ... 
         connectionStringName="LocalSqlServer" 
         ... />
       <add name="MySQLMembershipProvider" 
         autogenerateschema="true" 
         type="MySql.Web.Security.MySQLMembershipProvider, MySql.Web, Version=6.0.4.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" 
         connectionStringName="LocalMySqlServer" 
         ... />
     </providers>
    </membership>

    Note that the name for the connection string to be used to connect to the server that contains the membership database is LocalMySqlServer.

    The autogenerateschema="true" attribute will cause MySQL Connector/Net to silently create, or upgrade, the schema on the database server, to contain the required tables for storing membership information.

  7. It is now necessary to create the connection string referenced in the previous step. Load the web site's web.config file into Visual Studio.

  8. Locate the section marked <connectionStrings>. Add the following connection string information:

    <connectionStrings>
      <remove name="LocalMySqlServer"/>
      <add name="LocalMySqlServer"
           connectionString="Datasource=localhost;Database=users;uid=root;pwd=password;"
           providerName="MySql.Data.MySqlClient"/>
    </connectionStrings>

    The database specified is the one created in the first step. You could alternatively have used an existing database.

  9. At this point build the solution to ensure no errors are present. This can be done by selecting Build, Build Solution from the main menu, or pressing F6.

  10. ASP.NET supports the concept of locally and remotely authenticated users. With local authentication the user is validated using their Windows credentials when they attempt to access the web site. This can be useful in an Intranet environment. With remote authentication a user is prompted for their login details when accessing the web site, and these credentials are checked against the membership information stored in a database server such as MySQL Server. You will now see how to choose this form of authentication.

    Start the ASP.NET Web Site Administration Tool. This can be done quickly by clicking the small hammer/Earth icon in the Solution Explorer. You can also launch this tool by selecting Website, ASP.NET Configuration from the main menu.

  11. In the ASP.NET Web Site Administration Tool click the Security tab.

  12. Now click the User Authentication Type link.

  13. Select the From the internet radio button. The web site will now need to provide a form to allow the user to enter their login details. These will be checked against membership information stored in the MySQL database.

    Figure 21.31. Authentication Type

    Authentication Type
  14. You now need to specify the Role and Membership Provider to be used. Click the Provider tab.

  15. Click the Select a different provider for each feature (advanced) link.

  16. Now select the MySQLMembershipProvider and the MySQLRoleProvider radio buttons.

    Figure 21.32. Select Membership and Role Provider

    Select Membership and Role
              Provider
  17. In Visual Studio rebuild the solution by selecting Build, Rebuild Solution from the main menu.

  18. Check that the necessary schema has been created. This can be achieved using the MySQL Command Line Client program.

    Figure 21.33. Membership and Role Provider Tables

    Membership and Role Provider
              Tables
  19. Assuming all is present and correct you can now create users and roles for your web application. The easiest way to do this is with the ASP.NET Web Site Administration Tool. However, many web applications contain their own modules for creating roles and users. For simplicity the ASP.NET Web Site Administration Tool will be used in this tutorial.

  20. In the ASP.NET Web Site Administration Tool, click the Security tab. Now that both the Membership and Role Provider are enabled you will see links for creating roles and users. Click the Create or Manage Roles link.

    Figure 21.34. Security Tab

    Security Tab
  21. You can now enter the name of a new Role and click Add Role to create the new Role. Create new Roles as required.

  22. Click the Back button.

  23. Click the Create User link. You can now fill in information about the user to be created, and also allocate that user to one or more Roles.

    Figure 21.35. Create User

    Create User
  24. Using the MySQL Command Line Client program you can check that your database has been correctly populated with the Membership and Role data.

    Figure 21.36. Membership and Roles Table Contents

    Membership and Roles Table
              Contents

In this tutorial you have seen how to set up the MySQL Connector/Net Membership and Role Providers for use in your ASP.NET web application.

21.2.4.3. Tutorial: MySQL Connector/Net ASP.NET Session State Provider

MySQL Connector/Net from version 6.1 has included a MySQL Session State Provider. This provider enables you to store session state in a MySQL database. The following tutorial shows you how to prepare to use the MySQL Session State Provider, and then store session data into the MySQL database. This tutorial uses Microsoft Visual Studio 2008 Professional Edition, MySQL Connector/Net 6.1.1 and MySQL Server 5.1. This tutorial also assumes you have created an empty database, for example test, where you will store session data. You could do this using the MySQL Command Line Client tool.

  1. In Visual Studio create a new ASP.NET web site. If you are not sure how to do this refer to the tutorial Section 21.2.4.6, “Tutorial: Databinding in ASP.NET using LINQ on Entities” which demonstrates how to do this.

  2. Launch the MySQL MySQL Website Configuration tool. Due to a bug in 6.1.1 this may not appear unless you are connected to a server in the Server Explorer. If you are unfamiliar with the MySQL Website Configuration tool it is suggested that you first work through the following tutorial Section 21.2.3.10, “MySQL Website Configuration Tool”.

  3. Navigate through the wizard to the Session State page. Make sure the check box Use MySQL to manage my ASP.NET session data is selected.

  4. On the same page configure the connection string to the database that will contain your session data. This database can be empty as MySQL Connector/Net will create the schema required to store session data.

  5. Ensure that the check box Autogenerate Schema is selected so that MySQL Connector/Net will create the schema in your database to store the session data correctly.

  6. Enter the name of your application.

  7. Click Finish. The MySQL Website Configuration tool will now update your application's web.config file with information about the connection string and default providers to be used. In this case we have selected the MySQL Session State Provider.

At this point you are ready to use the MySQL database to store session data. To test that the set up has worked you can write a simple program that uses session variables.

  1. Open Default.aspx.cs. In the Page_Load method add the following code:

    Session["SessionVariable1"] = "Test string";
  2. Build your solution.

  3. Run the solution (without debugging). When the application runs, the provider will autogenerate tables required in the database you chose when setting up the application.

  4. Check that the schema was in fact created. Using the MySQL Command Line Client use the target database and then type SHOW TABLES;. You will see that MySQL Connector/Net has created the required schema automatically, as we selected this to happen in the MySQL Website Configuration tool.

  5. Now view the contents of these tables by typing SELECT * FROM my_aspnet_sessions; in the MySQL Command Line Client. This will display the session data our application used. Note that this is stored in binary format so some data may not display as expected.

At this point you have installed the Session State Provider and carried out a preliminary test of the installation. You will now work a bit more with the Session State Provider.

In this part of the tutorial you will set and retrieve a session variable. You can work with your existing project.

  1. Select the Default.aspx and switch to Design View. Add a text box and three buttons. Change the text property for the buttons to “Store Session Variable”, “Clear Textbox”, and “Show Session Variable”. These will be Button1, Button2 and Button3 respectively. Build your solution to ensure that no errors have been introduced.

  2. Still in the Design View, double-click Button1. Now to the Button1_Click event handler add code some the handler resembles the following:

    protected void Button1_Click(object sender, EventArgs e)
    {
        Session["SessionString"] = TextBox1.Text;
    }

    You have created a new Session variable accessed using the key “SessionString”. This will be set to the text that was entered into the text box when Button1 is clicked.

  3. In Design View double-click Button2 to add its click event handler. This button needs to clear text from the text box. The code to do this is as follows:

    protected void Button2_Click(object sender, EventArgs e)
    {
        TextBox1.Text = "";
    }

    The code simply assigns an empty string to the Text property of the text box.

  4. In the Design View double-click Button3 and modify the click handler as follows:

    protected void Button3_Click(object sender, EventArgs e)
    {
        TextBox1.Text = (String)Session["SessionString"];
    }

    This will retrieve the session string and display it in the text box.

  5. Now modify the Page_Load method as follows:

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
           TextBox1.Text = "Enter some text"; 
        }
    }

    This ensures that when the page loads the text box Text property is reset.

  6. Ensure that the solution is saved and then rebuild the solution.

  7. Run the solution without debugging.

  8. The form will be displayed. Enter some text into the text box. Now click Store Session Variable. At this point you have stored the string in a session variable.

  9. Now click Clear Text to clear the text box.

  10. Now click Show Session Variable to retrieve and display the session variable.

  11. Refresh the page to destroy the form and display a new form.

  12. Click Show Session Variable the text box will display the stored session variable, demonstrating that the refreshing the page does not destroy the session variable.

This illustrates that the session state data is not destroyed when a page is reloaded.

21.2.4.4. Tutorial: MySQL Connector/Net ASP.NET Profile Provider

This tutorial shows you how to use the MySQL Profile Provider to store user profile information in a MySQL database. The tutorial uses MySQL Connector/Net 6.1.1, MySQL Server 5.1 and Microsoft Visual Studio 2008 Professional Edition.

Many modern web sites allow the user to create a personal profile. This requires a significant amount of code, but ASP.NET reduces this considerable by including the functionality in its Profile classes. The Profile Provider provides an abstraction between these classes and a data source. The MySQL Profile Provider enables profile data to be stored in a MySQL database. This enables the profile properties to be written to a persistent store, and be retrieved when required. The Profile Provider also enables profile data to be managed effectively, for example it enables profiles that have not been accessed since a specific date to be deleted.

The following steps show you how you can select the MySQL Profile Provider.

  1. Create a new ASP.NET web project.

  2. Select the MySQL Website Configuration tool. Due to a bug in 6.1.1 you may have to first connect to a server in Server Explorer before the tool's icon will display in the toolbar of the Solution Explorer.

  3. In the MySQL Website Configuration tool navigate through the tool to the Profiles page.

  4. Select the Use MySQL to manage my profiles check box.

  5. Select the Autogenerate Schema check box.

  6. Click the Edit... button and configure a connection string for the database that will be used to store user profile information.

  7. Navigate to the last page of the tool and click Finish to save your changes and exit the tool.

At this point you are now ready to start using the MySQL Profile Provider. With the following steps you can carry out a preliminary test of your installation.

  1. Open your web.config file.

  2. Add a simple profile such as the following:

    <system.web>
      <anonymousIdentification enabled="true"/> 
      <profile defaultProvider="MySQLProfileProvider">
        ...
        <properties>
          <add name="Name" allowAnonymous="true"/>
          <add name="Age" allowAnonymous="true" type="System.UInt16"/>
          <group name="UI">
            <add name="Color" allowAnonymous="true" defaultValue="Blue"/>
            <add name="Style" allowAnonymous="true" defaultValue="Plain"/>
          </group>
        </properties>
      </profile>
      ...

    Note that anonymousIdentification has been set to true. This enables users who have not been authenticated to use profiles. They are identified by a GUID in a cookie rather than by user name.

Now that the simple profile has been defined in web.config, the next step is to write some code to test the profile.

  1. In Design View design a simple page with the following controls:

    Figure 21.37. Simple Profile Application

    Simple Profile Application

    These will allow the user to enter some profile information. The user can also use the buttons to save their profile, clear the page, and restore their profile data.

  2. In the Code View add code as follows:

    ...
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            TextBox1.Text = Profile.Name;
            TextBox2.Text = Profile.Age.ToString();
            Label1.Text = Profile.UI.Color;
        }
    }
    
    // Store Profile
    protected void Button1_Click(object sender, EventArgs e)
    {
        Profile.Name = TextBox1.Text;
        Profile.Age = UInt16.Parse(TextBox2.Text);
    }
    
    // Clear Form
    protected void Button2_Click(object sender, EventArgs e)
    {
        TextBox1.Text = "";
        TextBox2.Text = "";
        Label1.Text = "";
    }
    
    // Retrieve Profile
    protected void Button3_Click(object sender, EventArgs e)
    {
        TextBox1.Text = Profile.Name;
        TextBox2.Text = Profile.Age.ToString();
        Label1.Text = Profile.UI.Color;
    }
    
    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {
        Profile.UI.Color = DropDownList1.SelectedValue;
    }
    ...
  3. Save all files and build the solution to check that no errors have been introduced.

  4. Run the application.

  5. Enter your name, age and select a color from the listbox. Now store this information in your profile by clicking Store Profile. Note that if you do not select a color from the listbox your profile will use the default color Blue that was specified in the web.config file.

  6. Click Clear Form to clear text from the textboxes and the label that displays your chosen color.

  7. Now click Retrieve Profile to restore your profile data from the MySQL database.

  8. Now exit the browser to terminate the application.

  9. Run the application again. Note that when the page loads your profile information is restored from the MySQL database.

In this tutorial you have seen how to using the MySQL Profile Provider with MySQL Connector/Net.

21.2.4.5. Tutorial: Using an Entity Framework Entity as a Windows Forms Data Source

In this tutorial you will learn how to create a Windows Forms Data Source from an Entity in an Entity Data Model. This tutorial assumes that you have installed the World example database, which can be downloaded from the MySQL Documentation page. You can also find details on how to install the database on the same page. It will also be convenient for you to create a connection to the World database after it is installed. For instructions on how to do this see Section 21.2.3.1, “Making a connection”.

Creating a new Windows Forms application

The first step is to create a new Windows Forms application.

  1. In Visual Studio, select File, New, Project from the main menu.

  2. Choose the Windows Forms Application installed template. Click OK. The solution is created.

Adding an Entity Data Model

You will now add an Entity Data Model to your solution.

  1. In the Solution Explorer, right-click your application and select Add, New Item.... From Visual Studio installed templates select ADO.NET Entity Data Model. Click Add.

    Figure 21.38. Add Entity Data Model

    Add Entity Data Model
  2. You will now see the Entity Data Model Wizard. You will use the wizard to generate the Entity Data Model from the world example database. Select the icon Generate from database. Click След..

    Figure 21.39. Entity Data Model Wizard Screen 1

    Entity Data Model Wizard Screen
              1
  3. You can now select the connection you made earlier to the World database. If you have not already done so, you can create the new connection at this time by clicking New Connection.... For further instructions on creating a connection to a database see Section 21.2.3.1, “Making a connection”.

    Figure 21.40. Entity Data Model Wizard Screen 2

    Entity Data Model Wizard Screen
              2
  4. Make a note of the entity connection settings to be used in App.Config, as these will be used later to write the necessary control code.

  5. Click След..

  6. The Entity Data Model Wizard connects to the database. You are then presented with a tree structure of the database. From this you can select the object you would like to include in your model. If you had created Views and Stored Routines these will be displayed along with any tables. In this example you just need to select the tables. Click Finish to create the model and exit the wizard.

    Figure 21.41. Entity Data Model Wizard Screen 3

    Entity Data Model Wizard Screen
              3
  7. Visual Studio will generate the model and then display it.

    Figure 21.42. Entity Data Model Diagram

    Entity Data Model Diagram
  8. From the Visual Studio main menu select Build, Build Solution, to ensure that everything compiles correctly so far.

Adding a new Data Source

You will now add a new Data Source to your project and see how it can be used to read and write to the database.

  1. From the Visual Studio main menu select Data, Add New Data Source.... You will be presented with the Data Source Configuration Wizard.

    Figure 21.43. Entity Data Source Configuration Wizard Screen 1

    Entity Data Source Configuration Wizard
              Screen 1
  2. Select the Object icon. Click След..

  3. You will now select the Object to bind to. Expand the tree. In this tutorial, you will select the city table. Once the city table has been selected click След..

    Figure 21.44. Entity Data Source Configuration Wizard Screen 2

    Entity Data Source Configuration Wizard
              Screen 2
  4. The wizard will confirm that the city object is to be added. Click Finish.

    Figure 21.45. Entity Data Source Configuration Wizard Screen 3

    Entity Data Source Configuration Wizard
              Screen 3
  5. The city object will be display in the Data Sources panel. If the Data Sources panel is not displayed, select Data, Show Data Sources from the Visual Studio main menu. The docked panel will then be displayed.

    Figure 21.46. Data Sources

    Data Sources

Using the Data Source in a Windows Form

You will now learn how to use the Data Source in a Windows Form.

  1. In the Data Sources panel select the Data Source you just created and drag and drop it onto the Form Designer. By default the Data Source object will be added as a Data Grid View control. Note that the Data Grid View control is bound to the cityBindingSource and the Navigator control is bound to cityBindingNavigator.

    Figure 21.47. Data Form Designer

    Data Form Designer
  2. Save and rebuild the solution before continuing.

Adding Code to Populate the Data Grid View

You are now ready to add code to ensure that the Data Grid View control will be populated with data from the City database table.

  1. Double-click the form to access its code.

  2. Add code to instatiate the Entity Data Model's EntityContainer object and retrieve data from the database to populate the control.

    Figure 21.48. Adding Code to the Form

    Adding Code to the Form
  3. Save and rebuild the solution.

  4. Run the solution. Ensure the grid is populated and you can navigate the database.

    Figure 21.49. The Populated Grid Control

    The Populated Grid Control

Adding Code to Save Changes to the Database

You will now add code to enable you to save changes to the database.

The Binding source component ensures that changes made in the Data Grid View control are also made to the Entity classes bound to it. However, that data needs to be saved back from the entities to the database itself. This can be achieved by the enabling of the Save button in the Navigator control, and the addition of some code.

  1. In the Form Designer, click the Save icon in the Form toolbar and ensure that its Enabled property is set to True.

    Figure 21.50. Save Button Enabled

    Save Button Enabled
  2. Double-click the Save icon in the Form toolbar to display its code.

  3. You now need to add code to ensure that data is saved to the database when the save button is clicked in the application.

    Figure 21.51. Adding Save Code to the Form

    Adding Save Code to the Form
  4. Once the code has been added, save the solution and rebuild it. Run the application and verify that changes made in the grid are saved.

21.2.4.6. Tutorial: Databinding in ASP.NET using LINQ on Entities

In this tutorial you create an ASP.NET web page that binds LINQ queries to entities using the Entity Framework mapping.

If you have not already done so, install the World example database prior to attempting this tutorial. See the tutorial Section 21.2.4.5, “Tutorial: Using an Entity Framework Entity as a Windows Forms Data Source” for instructions on downloading and installing this database.

Creating an ASP.NET web site

In this part of the tutorial, you will create an ASP.NET web site. The web site will use the World database. The main web page will feature a drop down list from which you can select a country, data about that country's cities will then be displayed in a grid view control.

  1. From the Visual Studio main menu select File, New, Web Site....

  2. From the Visual Studio installed templates select ASP.NET Web Site. Click OK. You will be presented with the Source view of your web page by default.

  3. Click the Design view tab situated underneath the Source view panel.

    Figure 21.52. The Design Tab

    The Design Tab
  4. In the Design view panel, enter some text to decorate the blank web page.

  5. Click Toolbox. From the list of controls select DropDownList. Drag and drop the control to a location beneath the text on your web page.

    Figure 21.53. Drop Down List

    Drop Down List
  6. From the DropDownList control's context menu, ensure that the Enable AutoPostBack check box is enabled. This will ensure the control's event handler is called when an item is selected. The user's choice will in turn be used to populate the GridView control.

    Figure 21.54. Enable AutoPostBack

    Enable AutoPostBack
  7. From the Toolbox select the GridView control.

    Figure 21.55. Grid View Control

    Grid Vew Control

    Drag and drop the Grid Vew control to a location just below the Drop Down List you already placed.

    Figure 21.56. Placed Grid Vew Control

    Placed Grid View Control
  8. At this point it is recommended that you save your solution, and build the solution to ensure that there are no errors.

  9. If you run the solution you will see that the text and drop down list are displayed, but the list is empty. Also, the grid view does not appear at all. Adding this functionality is described in the following sections.

At this stage you have a web site that will build, but further functionality is required. The next step will be to use the Entity Framework to create a mapping from the World database into entities that you can control programmatically.

Creating an ADO.NET Entity Data Model

In this stage of the tutorial you will add an ADO.NET Entity Data Model to your project, using the World database at the storage level. The procedure for doing this is described in the tutorial Section 21.2.4.5, “Tutorial: Using an Entity Framework Entity as a Windows Forms Data Source”, and so will not be repeated here.

Populating a Drop Data List Box with using the results of a entity LINQ query

In this part of the tutorial you will write code to populate the DropDownList control. When the web page loads the data to populate the list will be achieved by using the results of a LINQ query on the model created previously.

  1. In the Design view panel, double-click any blank area. This brings up the Page_Load method.

  2. Modify the relevant section of code according to the following listing:

    ...
    public partial class _Default : System.Web.UI.Page
    {
        worldModel.worldEntities we;
    
        protected void Page_Load(object sender, EventArgs e)
        {
            we = new worldModel.worldEntities();
    
            if (!IsPostBack)
            {
                var countryQuery = from c in we.country
                                   orderby c.Name
                                   select new { c.Code, c.Name };
                DropDownList1.DataValueField = "Code";
                DropDownList1.DataTextField = "Name";
                DropDownList1.DataSource = countryQuery;
                DataBind();
            }
        }
    ...

    Note that the list control only needs to be populated when the page first loads. The conditional code ensures that if the page is subsequently reloaded, the list control is not repopulated, which would cause the user selection to be lost.

  3. Save the solution, build it and run it. You should see the list control has been populated. You can select an item, but as yet the grid view control does not appear.

At this point you have a working Drop Down List control, populated by a LINQ query on your entity data model.

Populating a Grid View control using an entity LINQ query

In the last part of this tutorial you will populate the Grid View Control using a LINQ query on your entity data model.

  1. In the Design view, double-click the DropDownList control. This causes its SelectedIndexChanged code to be displayed. This method is called when a user selects an item in the list control and thus fires an AutoPostBack event.

  2. Modify the relevant section of code accordingly to the following listing:

    ...
        protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
        {
            var cityQuery = from c in we.city
                            where c.CountryCode == DropDownList1.SelectedValue
                            orderby c.Name
                            select new { c.Name, c.Population, c.CountryCode };
            GridView1.DataSource = cityQuery;
            DataBind();
        }
    ...

    The grid view control is populated from the result of the LINQ query on the entity data model.

  3. As a check compare your code to that shown in the following screenshot:

    Figure 21.57. Source Code

    Source Code
  4. Save, build and run the solution. As you select a country you will see its cities are displayed in the grid view control.

    Figure 21.58. The Working Web Site

    The Working Web Site

In this tutorial you have seen how to create an ASP.NET web site, you have also seen how you can access a MySQL database using LINQ queries on an entity data model.

21.2.4.7. Tutorial: Using SSL with MySQL Connector/Net

In this tutorial you will learn how you can use MySQL Connector/Net to connect to a MySQL server configured to use SSL. Support for SSL client certificates was added with MySQL Connector/Net 6.2.

MySQL Server uses the PEM format for certificates and private keys. This tutorial will use the test certificates from the server test suite by way of example. You can obtain the MySQL Server source code from MySQL Downloads. The certificates can be found in the directory ./mysql-test/std_data.

To carry out the steps in this tutorial, you must have Open SSL installed. This can be downloaded for Microsoft Windows at no charge from Shining Light Productions.

Further details on the connection string options used in this tutorial can be found at Section 21.2.6, “Connector/Net Connection String Options Reference”.

Configuring the MySQL Server to use SSL

  1. In the MySQL Server configuration file, set the SSL parameters as follows:

    ssl-ca=path/to/repo/mysql-test/std_data/cacert.pem 
    ssl-cert=path/to/repo/mysql-test/std_data/server-cert.pem 
    ssl-key=path/to/repo/mysql-test/std_data/server-key.pem 

    Adjust the directories according to the location in which you installed the MySQL source code.

  2. In this step you create a test user and set the user to require SSL.

    Using the MySQL Command Line Client, connect as root and create the user sslclient.

  3. To set privileges and requirements, issue the following command:

    GRANT ALL PRIVILEGES ON *.* TO sslclient@'%' REQUIRE SSL;

Creating a certificate file to use with the .NET client

  1. The .NET client does not use the PEM file format, as .NET does not support this format natively. You will be using test client certificates from the same server repository, for the purposes of this example. Convert these to PFX format first. This format is also known as PKCS#12. An article describing this procedure can be found at the Citrix website. From the directory server-repository-root/mysql-test/std_data, issue the following command:

    openssl pkcs12 -export -in client-cert.pem -inkey client-key.pem -certfile cacert.pem -out client.pfx
  2. When asked for an export password, enter the password “pass”. The file client.pfx will be generated. This file is used in the remainder of the tutorial.

Connecting to the server using a file-based certificate

  1. You will use PFX file, client.pfx you created in the previous step to authenticate the client. The following example demonstrates how to connect using the SSL Mode, CertificateFile and CertificatePassword connection string options:

    using (MySqlConnection connection = new MySqlConnection( 
      "database=test;user=sslclient;" +  
      "CertificateFile=H:\\bzr\\mysql-trunk\\mysqlest\\std_data\\client.pfx" +  
      "CertificatePassword=pass;" + 
      "SSL Mode=Required ")) 
    { 
        connection.Open(); 
    }

    The path to the certificate file will need to be changed to reflect your individual installation.

Connecting to the server using a store-based certificate

  1. The first step is to import the PFX file, client.pfx, into the Personal Store. Double-click the file in Windows explorer. This launches the Certificate Import Wizard.

  2. Follow the steps dictated by the wizard, and when prompted for the password for the PFX file, enter “pass”.

  3. Click Finish to close the wizard and import the certificate into the personal store.

Examine certificates in the Personal Store

  1. Start the Microsoft Management Console by entering mmc.exe at a command prompt.

  2. Select File, Add/Remove snap-in. Click Add. Select Certificates from the list of available snap-ins in the dialog.

  3. Click Add button in the dialog, and select the My user account radio button. This is used for personal certificates.

  4. Click the Finish button.

  5. Click OK to close the Add/Remove Snap-in dialog.

  6. You will now have Certificates – Current User displayed in the left panel of the Microsoft Management Console. Expand the Certificates - Current User tree item and select Personal, Certificates. The right-hand panel will display a certificate issued to MySQL. This is the certificate that was previously imported. Double-click the certificate to display its details.

  7. After you have imported the certificate to the Personal Store, you can use a more succint connection string to connect to the database, as illustrated by the following code:

    using (MySqlConnection connection = new MySqlConnection( 
       "database=test;user=sslclient;" +  
       "Certificate Store Location=CurrentUser;" +  
       "SSL Mode=Required")) 
    { 
       connection.Open(); 
    }

Certificate Thumbprint Parameter

If you have a large number of certificates in your store, and many have the same Issuer, this can be a source of confusion and result in the wrong certificate being used. To alleviate this situation, there is an optional Certificate Thumbprint parameter that can additionally be specified as part of the connection string. As mentioned before, you can double-click a certificate in the Microsoft Management Console to display the certificate's details. When the Certificate dialog is displayed click the Details tab and scroll down to see the thumbprint. The thumbprint will typically be a number such as ‎47 94 36 00 9a 40 f3 01 7a 14 5c f8 47 9e 76 94 d7 aa de f0. This thumbprint can be used in the connection string, as the following code illustrates:

using (MySqlConnection connection = new MySqlConnection( 
      "database=test;user=sslclient;" + 
      "Certificate Store Location=CurrentUser;" + 
      "Certificate Thumbprint=479436009a40f3017a145cf8479e7694d7aadef0;"+ 
      "SSL Mode=Required")) 
{ 
    connection.Open(); 
}

Spaces in the thumbprint parameter are optional and the value is case-insensitive.

21.2.4.8. Tutorial: Using MySqlScript

This tutorial teaches you how to use the MySqlScript class. This class enables you to execute a series of statements. Depending on the circumstances, this can be more convenient than using the MySqlCommand approach.

Further details of the MySqlScript class can be found in the reference documentation supplied with MySQL Connector/Net.

To run the example programs in this tutorial, set up a simple test database and table using the mysql Command Line Client or MySQL Workbench. Commands for the mysql Command Line Client are given here:

  1. CREATE DATABASE TestDB;

  2. USE TestDB;

  3. CREATE TABLE TestTable (id INT NOT NULL PRIMARY KEY AUTO_INCREMENT, name VARCHAR(100));

The main method of the MySqlScript class is the Execute method. This method causes the script (sequence of statements) assigned to the Query property of the MySqlScript object to be executed. Note the Query property can be set through the MySqlScript constructor or using the Query property. Execute returns the number of statements executed.

The MySqlScript object will execute the specified script on the connection set using the Connection property. Again, this property can be set directly or through the MySqlScript constructor. The following code snippets illustrate this:

string sql = "SELECT * FROM TestTable";
...
MySqlScript script = new MySqlScript(conn, sql);
...
MySqlScript script = new MySqlScript();
script.Query = sql;
script.Connection = conn;
...
script.Execute();

The MySqlScript class has several events associated with it. There are:

  1. Error - generated if an error occurs.

  2. ScriptCompleted - generated when the script successfully completes execution.

  3. StatementExecuted - generated after each statement is executed.

It is possible to assign event handlers to each of these events. These user-provided routines are called back when the connected event occurs. The following code shows how the event handlers are set up.

script.Error += new MySqlScriptErrorEventHandler(script_Error);
script.ScriptCompleted += new EventHandler(script_ScriptCompleted);
script.StatementExecuted += new MySqlStatementExecutedEventHandler(script_StatementExecuted);

In VisualStudio, you can save typing by using tab completion to fill out stub routines. Start by typing, for example, “script.Error +=”. Then press TAB, and then press TAB again. The assignment is completed, and a stub event handler created. A complete working example is shown below:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Data;
using MySql.Data;
using MySql.Data.MySqlClient;

namespace MySqlScriptTest
{
    class Program
    {
        static void Main(string[] args)
        {
            string connStr = "server=localhost;user=root;database=TestDB;port=3306;password=******;";
            MySqlConnection conn = new MySqlConnection(connStr);

            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();

                string sql = "INSERT INTO TestTable(name) VALUES ('Superman');" +
                             "INSERT INTO TestTable(name) VALUES ('Batman');" +
                             "INSERT INTO TestTable(name) VALUES ('Wolverine');" +
                             "INSERT INTO TestTable(name) VALUES ('Storm');";

                MySqlScript script = new MySqlScript(conn, sql);

                script.Error += new MySqlScriptErrorEventHandler(script_Error);
                script.ScriptCompleted += new EventHandler(script_ScriptCompleted);
                script.StatementExecuted += new MySqlStatementExecutedEventHandler(script_StatementExecuted);

                int count = script.Execute();

                Console.WriteLine("Executed " + count + " statement(s).");
                Console.WriteLine("Delimiter: " + script.Delimiter);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }

            conn.Close();
            Console.WriteLine("Done.");
        }

        static void script_StatementExecuted(object sender, MySqlScriptEventArgs args)
        {
            Console.WriteLine("script_StatementExecuted");    
        }

        static void script_ScriptCompleted(object sender, EventArgs e)
        {
            /// EventArgs e will be EventArgs.Empty for this method 
            Console.WriteLine("script_ScriptCompleted!");
        }

        static void script_Error(Object sender, MySqlScriptErrorEventArgs args)
        {
            Console.WriteLine("script_Error: " + args.Exception.ToString());
        }
    }
}

Note that in the script_ScriptCompleted event handler, the EventArgs parameter e will be EventArgs.Empty. In the case of the ScriptCompleted event there is no additional data to be obtained, which is why the event object is EventArgs.Empty.

21.2.4.8.1. Using Delimiters with MySqlScript

Depending on the nature of the script, you may need control of the delimiter used to separate the statements that will make up a script. The most common example of this is where you have a multi-statement stored routine as part of your script. In this case if the default delimiter of “;” is used you will get an error when you attempt to execute the script. For example, consider the following stored routine:

CREATE PROCEDURE test_routine() 
BEGIN 
    SELECT name FROM TestTable ORDER BY name;
    SELECT COUNT(name) FROM TestTable;
END

This routine actually needs to be executed on the MySQL Server as a single statement. However, with the default delimiter of “;”, the MySqlScript class would interpret the above as two statements, the first being:

CREATE PROCEDURE test_routine() 
BEGIN 
    SELECT name FROM TestTable ORDER BY name;

Executing this as a statement would generate an error. To solve this problem MySqlScript supports the ability to set a different delimiter. This is achieved through the Delimiter property. For example, you could set the delimiter to “??”, in which case the above stored routine would no longer generate an error when executed. Multiple statements can be delimited in the script, so for example, you could have a three statement script such as:

string sql = "DROP PROCEDURE IF EXISTS test_routine??" +
             "CREATE PROCEDURE test_routine() " + 
             "BEGIN " + 
             "SELECT name FROM TestTable ORDER BY name;" + 
             "SELECT COUNT(name) FROM TestTable;" +
             "END??" +
             "CALL test_routine()";

You can change the delimiter back at any point by setting the Delimiter property. The following code shows a complete working example:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using MySql.Data;
using MySql.Data.MySqlClient;

namespace ConsoleApplication8
{
    class Program
    {
        static void Main(string[] args)
        {
            string connStr = "server=localhost;user=root;database=TestDB;port=3306;password=******;";
            MySqlConnection conn = new MySqlConnection(connStr);

            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();

                string sql =    "DROP PROCEDURE IF EXISTS test_routine??" +
                                "CREATE PROCEDURE test_routine() " + 
                                "BEGIN " + 
                                "SELECT name FROM TestTable ORDER BY name;" + 
                                "SELECT COUNT(name) FROM TestTable;" +
                                "END??" +
                                "CALL test_routine()";

                MySqlScript script = new MySqlScript(conn);

                script.Query = sql;
                script.Delimiter = "??";
                int count = script.Execute();
                Console.WriteLine("Executed " + count + " statement(s)");
                script.Delimiter = ";";
                Console.WriteLine("Delimiter: " + script.Delimiter);
                Console.WriteLine("Query: " + script.Query);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }

            conn.Close();
            Console.WriteLine("Done.");
        }
    }
}

21.2.4.9. Tutorial: Generating MySQL DDL from an Entity Framework Model

In this tutorial, you will learn how to create MySQL DDL from an Entity Framework model. Use Visual Studio 2010 and MySQL Connector/Net 6.3 to carry out this tutorial.

  1. Create a new console application in Visual Studio 2010.

  2. Using the Solution Explorer, add a reference to MySql.Data.Entity.

  3. From the Solution Explorer select Add, New Item. In the Add New Item dialog select Online Templates. Select ADO.NET Entity Data Model and click Add. The Entity Data Model dialog will be displayed.

  4. In the Entity Data Model dialog select Empty Model. Click Finish. A blank model will be created.

  5. Create a simple model. A single Entity will do for the purposes of this tutorial.

  6. In the Properties panel select ConceptualEntityModel from the drop-down listbox.

  7. In the Properties panel, locate the DDL Generation Template in the category Database Script Generation.

  8. For the DDL Generation property select SSDLToMySQL.tt(VS) from the drop-down listbox.

  9. Save the solution.

  10. Right-click an empty space in the model design area. The context-sensitive menu will be displayed.

  11. From the context-sensitive menu select Generate Database from Model. The Generate Database Wizard dialog will be displayed.

  12. In the Generate Database Wizard dialog select an existing connection, or create a new connection to a server. Select an appropriate radio button to show or hide sensitive data. For the purposes of this tutorial you can select Yes (although you might skip this for commercial applications).

  13. Click След.. MySQL compatible DDL code will be generated. Click Finish to exit the wizard.

You have seen how to create MySQL DDL code from an Entity Framework model.

21.2.5. Connector/Net Programming

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.

In the following sections you will learn about some common use cases for Connector/Net, including BLOB handling, date handling, and using Connector/Net with common tools such as Crystal Reports.

21.2.5.1. Connecting to MySQL Using Connector/Net

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.

21.2.5.2. Creating a Connection String

The MySqlConnection object is configured using a connection string. A connection string contains several key/value pairs, separated by semicolons. Each key/value pair is joined with an equal 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 user name of root and a password of 12345. The default database for all statements will be the test database. All other options may be found here: Section 21.2.6, “Connector/Net Connection String Options Reference”.

Замечание

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 21.2.6, “Connector/Net Connection String Options Reference”. The Old Синтаксис connection string option has now been deprecated.

21.2.5.2.1. 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.

Connector/NET can also connect using the native Windows authentication plugin. See Section 21.2.5.5, “Using the Native Windows Authentication Plugin” for further information.

Visual Basic Пример

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# Пример

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 Пример

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# Пример

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.

21.2.5.2.2. Handling Connection Ошибки

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 user name and/or password.

The following code shows how to adapt the application's response based on the actual error:

Visual Basic Пример

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# Пример

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;");
21.2.5.2.3. Using GetSchema on a Connection

The GetSchema() method of the connection object can be used to retrieve schema information about the database currently connected to. The schema information is returned in the form of a DataTable. The schema information is organized into a number of collections. Different forms of the GetSchema() method can be used depending on the information required. There are three forms of the GetSchema() method:

  • GetSchema() - This call will return a list of available collections.

  • GetSchema(String) - This call returns information about the collection named in the string parameter. If the string “MetaDataCollections” is used then a list of all available collections is returned. This is the same as calling GetSchema() without any parameters.

  • GetSchema(String, String[]) - In this call the first string parameter represents the collection name, and the second parameter represents a string array of restriction values. Restriction values limit the amount of data that will be returned. Restriction values are explained in more detail in the Microsoft .NET documentation.

21.2.5.2.3.1. Collections

The collections can be broadly grouped into two types: collections that are common to all data providers, and collections specific to a particular provider.

Common

The following collections are common to all data providers:

  • MetaDataCollections

  • DataSourceInformation

  • DataTypes

  • Restrictions

  • ReservedWords

Provider-specific

The following are the collections currently provided by MySQL Connector/Net, in addition to the common collections above:

  • Databases

  • Tables

  • Columns

  • Users

  • Foreign Keys

  • IndexColumns

  • Indexes

  • Foreign Key Columns

  • UDF

  • Views

  • ViewColumns

  • Procedure Parameters

  • Procedures

  • Triggers

Пример Code

A list of available collections can be obtained using the following code:

using System;
using System.Data;
using System.Text;
using MySql.Data;
using MySql.Data.MySqlClient;

namespace ConsoleApplication2
{
    class Program
    {

        private static void DisplayData(System.Data.DataTable table)
        {
            foreach (System.Data.DataRow row in table.Rows)
            {
                foreach (System.Data.DataColumn col in table.Columns)
                {
                    Console.WriteLine("{0} = {1}", col.ColumnName, row[col]);
                }
                Console.WriteLine("============================");
            }
        }

        static void Main(string[] args)
        {

            string connStr = "server=localhost;user=root;database=world;port=3306;password=******;";
            MySqlConnection conn = new MySqlConnection(connStr);

            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();

                DataTable table = conn.GetSchema("MetaDataCollections");
                //DataTable table = conn.GetSchema("UDF");
                DisplayData(table);

                conn.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            Console.WriteLine("Done.");
        }
    }
}

Further information on the GetSchema() method and schema collections can be found in the Microsoft .NET documentation.

21.2.5.3. Using MySqlCommand

A MySqlCommand has the CommandText and CommandType properties associated with it. The CommandText will be handled differently depending on the setting of CommandType. CommandType can be one of:

  1. Text - A SQL text command (default)

  2. StoredProcedure - The name of a Stored Procedure

  3. TableDirect - The name of a table (new in Connector/Net 6.2)

The default CommandType, Text, is used for executing queries and other SQL commands. Some example of this can be found in the following section Section 21.2.4.1.2, “The MySqlCommand Object”.

If CommandType is set to StoredProcedure, set CommandText to the name of the Stored Procedure to access.

If CommandType is set to TableDirect, all rows and columns of the named table will be returned when you call one of the Execute methods. In effect, this command performs a SELECT * on the table specified. The CommandText property is set to the name of the table to query. This is illustrated by the following code snippet:

...
MySqlCommand cmd = new MySqlCommand();
cmd.CommandText = "mytable";
cmd.Connection = someConnection;
cmd.CommandType = CommandType.TableDirect;
MySqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
   Console.WriteLn(reader[0], reader[1]...);
}
...

Examples of using the CommandType of StoredProcedure can be found in the section Section 21.2.5.8, “Accessing Stored Procedures with Connector/Net”.

Commands can have a timeout associated with them. This is useful as you may not want a situation were a command takes up an excessive amount of time. A timeout can be set using the CommandTimeout property. The following code snippet sets a timeout of one minute:

MySqlCommand cmd = new MySqlCommand();
cmd.CommandTimeout = 60;

The default value is 30 seconds. Avoid a value of 0, which indicates an indefinite wait. To change the default command timeout, use the connection string option Default Command Timeout.

Prior to MySQL Connector/Net 6.2, MySqlCommand.CommandTimeout included user processing time, that is processing time not related to direct use of the connector. Timeout was implemented through a .NET Timer, that triggered after CommandTimeout seconds. This timer consumed a thread.

MySQL Connector/Net 6.2 introduced timeouts that are aligned with how Microsoft handles SqlCommand.CommandTimeout. This property is the cumulative timeout for all network reads and writes during command execution or processing of the results. A timeout can still occur in the MySqlReader.Read method after the first row is returned, and does not include user processing time, only IO operations. The 6.2 implementation uses the underlying stream timeout facility, so is more efficient in that it does not require the additional timer thread as was the case with the previous implementation.

Further details on this can be found in the relevant Microsoft documentation.

21.2.5.4. Using Connector/Net with Connection Pooling

The Connector/Net supports connection pooling. This is enabled by default, but can be turned off using connection string options. See Section 21.2.5.2, “Creating a Connection String” for further information.

Connection pooling works by keeping the native connection to the server live when the client disposes of a MySqlConnection. Subsequently, if a new MySqlConnection object is opened, it will be created from the connection pool, rather than creating a new native connection. This improves performance.

To work as designed, it is best to let the connection pooling system manage all connections. Do not create a globally accessible instance of MySqlConnection and then manually open and close it. This interferes with the way the pooling works and can lead to unpredictable results or even exceptions.

One approach that simplifies things is to avoid manually creating a MySqlConnection object. Instead use the overloaded methods that take a connection string as an argument. Using this approach, Connector/Net will automatically create, open, close and destroy connections, using the connection pooling system for best performance.

Typed Datasets and the MembershipProvider and RoleProvider classes use this approach. Most classes that have methods that take a MySqlConnection as an argument, also have methods that take a connection string as an argument. This includes MySqlDataAdapter.

Instead of manually creating MySqlCommand objects, you can use the static methods of the MySqlHelper class. These take a connection string as an argument, and they fully support connection pooling.

Starting with MySQL Connector/Net 6.2, there is a background job that runs every three minutes and removes connections from pool that have been idle (unused) for more than three minutes. The pool cleanup frees resources on both client and server side. This is because on the client side every connection uses a socket, and on the server side every connection uses a socket and a thread.

Prior to this change, connections were never removed from the pool, and the pool always contained the peak number of open connections. For example, a web application that peaked at 1000 concurrent database connections would consume 1000 threads and 1000 open sockets at the server, without ever freeing up those resources from the connection pool. Note, connections, no matter how old, will not be closed if the number of connections in the pool is less than or equal to the value set by the Min Pool Size connection string parameter.

21.2.5.5. Using the Native Windows Authentication Plugin

Section 5.5.6.3, “The Windows Native Authentication Plugin” is supported as of Connector/NET 6.4.4.

The interface matches the MySql.Data.MySqlClient object. To enable, pass in Integrated Security to the connection string with a value of yes or sspi.

Passing in a user ID is optional. When Windows authentication is set up, a MySQL user is created and configured to be used by Windows authentication. By default, this user ID is named auth_windows, but can be defined using a different name. If the default name is used, then passing the user ID to the connection string from Connector/NET is optional, because it will use the auth_windows user. Otherwise, the name must be passed to the connection string using the standard user ID element.

21.2.5.6. Using Connector/Net with Table Caching

This feature exists with Connector/NET versions 6.4 and above.

Table caching is a feature that can be used to cache slow-changing datasets on the client side. This is useful for applications that are designed to use readers, but still want to minimize trips to the server for slow-changing tables.

This feature is transparent to the user, and is disabled by default.

Configuration
  • To enable table caching, add 'table cache = true' to the connection string.

  • Optionally, specify the 'Default Table Cache Age' connection string option, which represents the number of seconds a table is cached before the cached data is discarded. The default value is 60.

  • You can caching on and off and set caching options at runtime, on a per command basis.

21.2.5.7. Using the Connector/Net with Prepared Statements

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.

21.2.5.7.1. 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 Пример

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.AddWithValue("@number", 1)
   cmd.Parameters.AddWithValue("@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# Пример

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.AddWithValue("@number", 1);
    cmd.Parameters.AddWithValue("@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);
}

21.2.5.8. Accessing Stored Procedures with Connector/Net

Introduction

MySQL server version 5 and up supports stored procedures with the SQL 2003 stored procedure syntax.

A stored procedure is a set of SQL statements that is stored in the server. Clients make a single call to the stored procedure, passing parameters that can influence the procedure logic and query conditions, rather than issuing individual hardcoded SQL statements.

Stored procedures can be particularly useful in situations such as the following:

  • Stored procedures can act as an API or abstraction layer, allowing multiple client applications to perform the same database operations. The applications can be written in different languages and run on different platforms. The applications do not need to hardcode table and column names, complicated queries, and so on. When you extend and optimize the queries in a stored procedure, all the applications that call the procedure automatically receive the benefits.

  • When security is paramount, stored procedures keep applications from directly manipulating tables, or even knowing details such as table and column names. 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 out of a MySQL stored procedure through use of the MySqlCommand.Parameters collection.

Замечание

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-routines.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.

21.2.5.8.1. Using Stored Routines 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 MySQL Workbench. Finally, stored procedures can be created using the .ExecuteNonQuery method of the MySqlCommand object.

Unlike the command-line and GUI clients, you are not required to specify a special delimiter when creating stored procedures in Connector/Net.

To call a stored procedure using Connector/Net, you create a MySqlCommand object and pass the stored procedure name as the .CommandText property. You then set the .CommandType property to CommandType.StoredProcedure.

After the stored procedure is named, you 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 data type that is expected to be returned. All parameters need the parameter direction defined.

After defining the parameters, you call the stored procedure by using the MySqlCommand.ExecuteNonQuery() method.

Once the stored procedure is called, the values of the output parameters can be retrieved by using the .Value property of the MySqlConnector.Parameters collection.

Замечание

When a stored procedure is called using MySqlCommand.ExecuteReader, and the stored procedure has output parameters, the output parameters are only set after the MySqlDataReader returned by ExecuteReader is closed.

The following C# example code demonstrates the use of stored procedures. It assumes the database 'employees' has already been created:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Data;
using MySql.Data;
using MySql.Data.MySqlClient;

namespace UsingStoredRoutines
{
    class Program
    {
        static void Main(string[] args)
        {
            MySqlConnection conn = new MySqlConnection();
            conn.ConnectionString = "server=localhost;user=root;database=employees;port=3306;password=******;";
            MySqlCommand cmd = new MySqlCommand();

            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();
                cmd.Connection = conn;
                cmd.CommandText = "DROP PROCEDURE IF EXISTS add_emp";
                cmd.ExecuteNonQuery();
                cmd.CommandText = "DROP TABLE IF EXISTS emp";
                cmd.ExecuteNonQuery();
                cmd.CommandText = "CREATE TABLE emp (empno INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY, first_name VARCHAR(20), last_name VARCHAR(20), birthdate DATE)";
                cmd.ExecuteNonQuery();

                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 (MySqlException ex)
            {
                Console.WriteLine ("Error " + ex.Number + " has occurred: " + ex.Message);
            }
            conn.Close();
            Console.WriteLine("Connection closed.");
            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();
                cmd.Connection = conn;

                cmd.CommandText = "add_emp";
                cmd.CommandType = CommandType.StoredProcedure;

                cmd.Parameters.AddWithValue("@lname", "Jones");
                cmd.Parameters["@lname"].Direction = ParameterDirection.Input;

                cmd.Parameters.AddWithValue("@fname", "Tom");
                cmd.Parameters["@fname"].Direction = ParameterDirection.Input;

                cmd.Parameters.AddWithValue("@bday", "1940-06-07");
                cmd.Parameters["@bday"].Direction = ParameterDirection.Input;

                cmd.Parameters.AddWithValue("@empno", MySqlDbType.Int32);
                cmd.Parameters["@empno"].Direction = ParameterDirection.Output;

                cmd.ExecuteNonQuery();

                Console.WriteLine("Employee number: "+cmd.Parameters["@empno"].Value);
                Console.WriteLine("Birthday: " + cmd.Parameters["@bday"].Value);
            }
            catch (MySql.Data.MySqlClient.MySqlException ex)
            {
                Console.WriteLine("Error " + ex.Number + " has occurred: " + ex.Message);
            }
            conn.Close();
            Console.WriteLine("Done.");
        }
    }
}

The following code shows the same application in Visual Basic:

Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text

Imports System.Data
Imports MySql.Data
Imports MySql.Data.MySqlClient

Module Module1

    Sub Main()
        Dim conn As New MySqlConnection()
        conn.ConnectionString = "server=localhost;user=root;database=world;port=3306;password=******;"
        Dim cmd As New MySqlCommand()

        Try
            Console.WriteLine("Connecting to MySQL...")
            conn.Open()
            cmd.Connection = conn
            cmd.CommandText = "DROP PROCEDURE IF EXISTS add_emp"
            cmd.ExecuteNonQuery()
            cmd.CommandText = "DROP TABLE IF EXISTS emp"
            cmd.ExecuteNonQuery()
            cmd.CommandText = "CREATE TABLE emp (empno INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY, first_name VARCHAR(20), last_name VARCHAR(20), birthdate DATE)"
            cmd.ExecuteNonQuery()

            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
            Console.WriteLine(("Error " & ex.Number & " has occurred: ") + ex.Message)
        End Try
        conn.Close()
        Console.WriteLine("Connection closed.")
        Try
            Console.WriteLine("Connecting to MySQL...")
            conn.Open()
            cmd.Connection = conn

            cmd.CommandText = "add_emp"
            cmd.CommandType = CommandType.StoredProcedure

            cmd.Parameters.AddWithValue("@lname", "Jones")
            cmd.Parameters("@lname").Direction = ParameterDirection.Input

            cmd.Parameters.AddWithValue("@fname", "Tom")
            cmd.Parameters("@fname").Direction = ParameterDirection.Input

            cmd.Parameters.AddWithValue("@bday", "1940-06-07")
            cmd.Parameters("@bday").Direction = ParameterDirection.Input

            cmd.Parameters.AddWithValue("@empno", MySqlDbType.Int32)
            cmd.Parameters("@empno").Direction = ParameterDirection.Output

            cmd.ExecuteNonQuery()

            Console.WriteLine("Employee number: " & cmd.Parameters("@empno").Value)
            Console.WriteLine("Birthday: " & cmd.Parameters("@bday").Value)
        Catch ex As MySql.Data.MySqlClient.MySqlException
            Console.WriteLine(("Error " & ex.Number & " has occurred: ") + ex.Message)
        End Try
        conn.Close()
        Console.WriteLine("Done.")

    End Sub

End Module

21.2.5.9. Handling BLOB Data With Connector/Net

Introduction

One common use for MySQL is the storage of binary data in BLOB columns. MySQL supports four different BLOB data types: TINYBLOB, BLOB, MEDIUMBLOB, and LONGBLOB, all described in Section 10.4.3, “The BLOB and TEXT Types” and Section 10.5, “Data Type Storage Requirements”.

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.

21.2.5.9.1. 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 file name, 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 might need to modify the max_allowed_packet system variable. This variable determines how large of a packet (that is, a single row) can be sent to the MySQL server. By default, the server only accepts a maximum size of 1MB from the client application. If you intend to exceed 1MB in your file transfers, increase this number.

The max_allowed_packet option can be modified using MySQL Administrator's Startup Variables screen. Adjust the Maximum permitted 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.

21.2.5.9.2. 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 Пример

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.AddWithValue("@FileName", strFileName)
    cmd.Parameters.AddWithValue("@FileSize", FileSize)
    cmd.Parameters.AddWithValue("@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# Пример

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.AddWithValue("@FileName", strFileName);
    cmd.Parameters.AddWithValue("@FileSize", FileSize);
    cmd.Parameters.AddWithValue("@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.

21.2.5.9.3. 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 Пример

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# Пример

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.

21.2.5.10. Using Connector/Net with Crystal Reports

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.

21.2.5.10.1. 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 Пример

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# Пример

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.

21.2.5.10.2. Creating the Report

For most purposes, the Standard Report wizard helps 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 first prompts you for a data source. If you use 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.

21.2.5.10.3. 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:

  • CrystalDecisions.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 21.2.5.10.1, “Creating a Data Source”, and have a crViewer control on your form named myViewer.

Visual Basic Пример

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# Пример

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 enables 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 Пример

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# Пример

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 alphabetic 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.

21.2.5.11. Handling Date and Time Information in Connector/Net

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.

21.2.5.11.1. 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.

21.2.5.11.2. 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 5.1.6, “Server SQL Modes”.

21.2.5.11.3. 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 data type.

The MySqlDateTime data type 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.

21.2.5.11.4. Handling NULL Dates

The .NET DateTime data type 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 Пример

If Not myReader.IsDBNull(myReader.GetOrdinal("mytime")) Then
    myTime = myReader.GetDateTime(myReader.GetOrdinal("mytime"))
Else
    myTime = DateTime.MinValue
End If
  

C# Пример

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.

21.2.5.12. ASP.NET Provider Model

MySQL Connector/Net provides support for the ASP.NET 2.0 provider model. This model enables application developers to focus on the business logic of their application instead of having to recreate such boilerplate items as membership and roles support.

MySQL Connector/Net supplies the following providers:

  • Membership Provider

  • Role Provider

  • Profile Provider

  • Session State Provider (MySQL Connector/Net 6.1 and later)

The following tables show the supported providers, their default provider and the corresponding MySQL provider.

Membership Provider

Default ProviderMySQL Provider
System.Web.Security.SqlMembershipProviderMySql.Web.Security.MySQLMembershipProvider

Role Provider

Default ProviderMySQL Provider
System.Web.Security.SqlRoleProviderMySql.Web.Security.MySQLRoleProvider

Profile Provider

Default ProviderMySQL Provider
System.Web.Profile.SqlProfileProviderMySql.Web.Profile.MySQLProfileProvider

SessionState Provider

Default ProviderMySQL Provider
System.Web.SessionState.InProcSessionStateStoreMySql.Web.SessionState.MySqlSessionStateStore
Замечание

The MySQL Session State provider uses slightly different capitalization on the class name compared to the other MySQL providers.

Installing The Providers

The installation of Connector/Net 5.1 or later will install the providers and register them in your machine's .NET configuration file, machine.config. The additional entries created will result in the system.web section appearing similar to the following code:

<system.web>
  <processModel autoConfig="true" />
  <httpHandlers />
  <membership>
    <providers>
      <add name="AspNetSqlMembershipProvider" type="System.Web.Security.SqlMembershipProvider, System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" connectionStringName="LocalSqlServer" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="true" applicationName="/" requiresUniqueEmail="false" passwordFormat="Hashed" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="7" minRequiredNonalphanumericCharacters="1" passwordAttemptWindow="10" passwordStrengthRegularExpression="" />
      <add name="MySQLMembershipProvider" type="MySql.Web.Security.MySQLMembershipProvider, MySql.Web, Version=6.1.1.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" connectionStringName="LocalMySqlServer" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="true" applicationName="/" requiresUniqueEmail="false" passwordFormat="Clear" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="7" minRequiredNonalphanumericCharacters="1" passwordAttemptWindow="10" passwordStrengthRegularExpression="" />
    </providers>
  </membership>
  <profile>
    <providers>
      <add name="AspNetSqlProfileProvider" connectionStringName="LocalSqlServer" applicationName="/" type="System.Web.Profile.SqlProfileProvider, System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
      <add name="MySQLProfileProvider" type="MySql.Web.Profile.MySQLProfileProvider, MySql.Web, Version=6.1.1.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" connectionStringName="LocalMySqlServer" applicationName="/" />
    </providers>
  </profile>
  <roleManager>
    <providers>
      <add name="AspNetSqlRoleProvider" connectionStringName="LocalSqlServer" applicationName="/" type="System.Web.Security.SqlRoleProvider, System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
      <add name="AspNetWindowsTokenRoleProvider" applicationName="/" type="System.Web.Security.WindowsTokenRoleProvider, System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
      <add name="MySQLRoleProvider" type="MySql.Web.Security.MySQLRoleProvider, MySql.Web, Version=6.1.1.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" connectionStringName="LocalMySqlServer" applicationName="/" />
    </providers>
  </roleManager>
</system.web>

Each provider type can have multiple provider implementations. The default provider can also be set here using the defaultProvider attribute, but usually this is set in the web.config file either manually or by using the ASP.NET configuration tool.

At time of writing, the MySqlSessionStateStore is not added to machine.config at install time, and so add the following:

<sessionState>
  <providers>
    <add name="MySqlSessionStateStore" type="MySql.Web.SessionState.MySqlSessionStateStore, MySql.Web, Version=6.1.1.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" connectionStringName="LocalMySqlServer" applicationName="/" />
  </providers>
</sessionState>

The SessionState Provider uses the customProvider attribute, rather than defaultProvider, to set the provider as the default. A typical web.config file might contain:

   <system.web>
        <membership defaultProvider="MySQLMembershipProvider" />
        <roleManager defaultProvider="MySQLRoleProvider" />
        <profile defaultProvider="MySQLProfileProvider" />
        <sessionState customProvider="MySqlSessionStateStore" />
        <compilation debug="false">
          ...

This sets the MySQL Providers as the defaults to be used in this web application.

The providers are implemented in the file mysql.web.dll and this file can be found in your MySQL Connector/Net installation folder. There is no need to run any type of SQL script to set up the database schema, as the providers create and maintain the proper schema automatically.

Using The Providers

The easiest way to start using the providers is to use the ASP.NET configuration tool that is available on the Solution Explorer toolbar when you have a website project loaded.

In the web pages that open, you can select the MySQL membership and roles providers by picking a custom provider for each area.

When the provider is installed, it creates a dummy connection string named LocalMySqlServer. Although this has to be done so that the provider will work in the ASP.NET configuration tool, you override this connection string in your web.config file. You do this by first removing the dummy connection string and then adding in the proper one, as shown in the following example:

<connectionStrings>
  <remove name="LocalMySqlServer"/>
  <add name="LocalMySqlServer" connectionString="server=xxx;uid=xxx;pwd=xxx;database=xxx;"/>
</connectionStrings>

Note the database to connect to must be specified.

Rather than manually editing configuration files, consider using the MySQL Website Configuration tool to configure your desired provider setup. From MySQL Connector/Net 6.1.1 onwards, all providers can be selected and configured from this wizard. The tool modifies your website.config file to the desired configuration. A tutorial on doing this is available in the following section Section 21.2.3.10, “MySQL Website Configuration Tool”.

A tutorial demonstrating how to use the Membership and Role Providers can be found in the following section Section 21.2.4.2, “Tutorial: MySQL Connector/Net ASP.NET Membership and Role Provider”.

Deployment

To use the providers on a production server, distribute the MySql.Data and the MySql.Web assemblies, and either register them in the remote systems Global Assembly Cache or keep them in your application's bin/ directory.

21.2.5.13. Binary/Nonbinary Issues

There are certain situations where MySQL will return incorrect metadata about one or more columns. More specifically, the server will sometimes report that a column is binary when it is not and vice versa. In these situations, it becomes practically impossible for the connector to be able to correctly identify the correct metadata.

Some examples of situations that may return incorrect metadata are:

  • Execution of SHOW PROCESSLIST. Some of the columns will be returned as binary even though they only hold string data.

  • When a temporary table is used to process a resultset, some columns may be returned with incorrect binary flags.

  • Some server functions such DATE_FORMAT will incorrectly return the column as binary.

With the availability of BINARY and VARBINARY data types, it is important that we respect the metadata returned by the server. However, we are aware that some existing applications may break with this change, so we are creating a connection string option to enable or disable it. By default, Connector/Net 5.1 respects the binary flags returned by the server. You might need to make small changes to your application to accommodate this change.

In the event that the changes required to your application would be too large, adding 'respect binary flags=false' to your connection string causes the connector to use the prior behavior: any column that is marked as string, regardless of binary flags, will be returned as string. Only columns that are specifically marked as a BLOB will be returned as BLOB.

21.2.5.14. Character Sets

Treating Binary Blobs As UTF8

MySQL doesn't currently support 4-byte UTF8 sequences. This makes it difficult to represent some multi-byte languages such as Japanese. To try and alleviate this, Connector/Net now supports a mode where binary blobs can be treated as strings.

To do this, you set the 'Treat Blobs As UTF8' connection string keyword to yes. This is all that needs to be done to enable conversion of all binary blobs to UTF8 strings. To convert only some of your BLOB columns, you can make use of the 'BlobAsUTF8IncludePattern' and'BlobAsUTF8ExcludePattern' keywords. Set these to a regular expression pattern that matches the column names to include or exclude respectively.

When the regular expression patterns both match a single column, the include pattern is applied before the exclude pattern. The result, in this case, would be that the column would be excluded. Also, be aware that this mode does not apply to columns of type BINARY or VARBINARY and also do not apply to nonbinary BLOB columns.

Currently, this mode only applies to reading strings out of MySQL. To insert 4-byte UTF8 strings into blob columns, use the .NET Encoding.GetBytes function to convert your string to a series of bytes. You can then set this byte array as a parameter for a BLOB column.

21.2.5.15. Working with Partial Trust

.NET applications operate under a given trust level. Normal desktop applications operate under full trust, while web applications that are hosted in shared environments are normally run under the partial trust level (sometimes known as “medium trust”). Some hosting providers host shared applications in their own app pools and allow the application to run under full trust, but this configuration is relatively rare.

Connector/Net versions prior to 5.0.8 and 5.1.3 were not compatible with partial trust hosting. Starting with these versions, Connector/Net can be used under partial trust hosting that has been modified to allow the use of sockets for communication. By default, partial trust does not include SocketPermission. Connector/Net uses sockets to talk with the MySQL server so it is required that a new trust level be created that is an exact clone of partial trust but that has SocketPermission added.

21.2.5.16. Using the MySQL Connector/Net Trace Source Object

MySQL Connector/Net 6.2 introduced support for .NET 2.0 compatible tracing, using TraceSource objects.

The .NET 2.0 tracing architecture consists of four main parts:

  • Source - This is the originator of the trace information. The source is used to send trace messages. The name of the source provided by MySQL Connector/Net is mysql.

  • Switch - This defines the level of trace information to emit. Typically, this is specified in the app.config file, so that it is not necessary to recompile an application to change the trace level.

  • Listener - Trace listeners define where the trace information will be written to. Supported listeners include, for example, the Visual Studio Output window, the Windows Event Log, and the console.

  • Filter - Filters can be attached to listeners. Filters determine the level of trace information that will be written. While a switch defines the level of information that will be written to all listeners, a filter can be applied on a per-listener basis, giving finer grained control of trace information.

To use tracing a TraceSource object first needs to be created. To create a TraceSource object in MySQL Connector/Net you would use code similar to the following:

TraceSource ts = new TraceSource("mysql");

To enable trace messages, configure a trace switch. There are three main switch classes, BooleanSwitch, SourceSwitch, and TraceSwitch. Trace switches also have associated with them a trace level enumeration, these are Off, Error, Warning, Info, and Verbose. The following code snippet illustrates creating a switch:

ts.Switch = new SourceSwitch("MySwitch", "Verbose");

This creates a SourceSwitch, called MySwitch, and sets the trace level to Verbose, meaning that all trace messages will be written.

It is convenient to be able to change the trace level without having to recompile the code. This is achieved by specifying the trace level in application configuration file, app.config. You then simply need to specify the desired trace level in the configuration file and restart the application. The trace source is configured within the system.diagnostics section of the file. The following XML snippet illustrates this:

<configuration>
  ...
  <system.diagnostics>
    <sources>
      <source name="mysql" switchName="MySwitch"
              switchType="System.Diagnostics.SourceSwitch" />
      ...
    </sources>
    <switches>
      <add name="MySwitch" value="Verbose"/>
      ...
    </switches>
  </system.diagnostics>
  ...
</configuration>

By default, trace information is written to the Output window of Microsoft Visual Studio. There are a wide range of listeners that can be attached to the trace source, so that trace messages can be written out to various destinations. You can also create custom listeners to allow trace messages to be written to other destinations as mobile devices and web services. A commonly used example of a listener is ConsoleTraceListener, which writes trace messages to the console.

To add a listener at run time, use code such as the following:

ts.Listeners.Add(new ConsoleTraceListener());

Then, call methods on the trace source object to generate trace information. For example, the TraceInformation(), TraceEvent(), or TraceData() methods can be used.

The TraceInformation() method simply prints a string passed as a parameter. The TraceEvent() method, as well as the optional informational string, requires a TraceEventType value to be passed to indicate the trace message type, and also an application specific ID. The TraceEventType can have a value of Verbose, Information, Warning, Error, and Critical. Using the TraceData() method you can pass any object, for example an exception object, instead of a message.

To ensure than these generated trace messages gets flushed from the trace source buffers to listeners, invoke the Flush() method. When you are finished using a trace source, call the Close() method. The Close() method first calls Flush(), to ensure any remaining data is written out. It then frees up resources, and closes the listeners associated with the trace source.

ts.TraceInformation("Informational message");
ts.TraceEvent(TraceEventType.Error, 3, "Optional error message");
ts.TraceData(TraceEventType.Error, 3, ex); // pass exception object
ts.Flush();
...
ts.Close();
21.2.5.16.1. Viewing MySQL Trace Information

This section describes how to set up your application to view MySQL trace information.

The first thing you need to do is create a suitable app.config file for your application. An example is shown in the following code:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.diagnostics>
    <sources>
      <source name="mysql" switchName="SourceSwitch"
        switchType="System.Diagnostics.SourceSwitch" >
        <listeners>
          <add name="console" />
          <remove name ="Default" />
        </listeners>
      </source>
    </sources>
    <switches>
      <!-- You can set the level at which tracing is to occur -->
      <add name="SourceSwitch" value="Verbose" />
      <!-- You can turn tracing off -->
      <!--add name="SourceSwitch" value="Off" -->
    </switches>
    <sharedListeners>
      <add name="console"
        type="System.Diagnostics.ConsoleTraceListener"
        initializeData="false"/>
    </sharedListeners>
  </system.diagnostics>
</configuration>

This ensures a suitable trace source is created, along with a switch. The switch level in this case is set to Verbose to display the maximum amount of information.

In the application the only other step required is to add logging=true to the connection string. An example application could be:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using MySql.Data;
using MySql.Data.MySqlClient;
using MySql.Web;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {

            string connStr = "server=localhost;user=root;database=world;port=3306;password=******;logging=true;";
            MySqlConnection conn = new MySqlConnection(connStr);
            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();

                string sql = "SELECT Name, HeadOfState FROM Country WHERE Continent='Oceania'";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                MySqlDataReader rdr = cmd.ExecuteReader();

                while (rdr.Read())
                {
                    Console.WriteLine(rdr[0] + " -- " + rdr[1]);
                }

                rdr.Close();

                conn.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            Console.WriteLine("Done.");
        }
    }
}

This simple application will then generate the following output:

Connecting to MySQL...
mysql Information: 1 : 1: Connection Opened: connection string = 'server=localhost;User Id=root;database=world;port=3306
;password=******;logging=True'
mysql Information: 3 : 1: Query Opened: SHOW VARIABLES
mysql Information: 4 : 1: Resultset Opened: field(s) = 2, affected rows = -1, inserted id = -1
mysql Information: 5 : 1: Resultset Closed. Total rows=272, skipped rows=0, size (bytes)=7058
mysql Information: 6 : 1: Query Closed
mysql Information: 3 : 1: Query Opened: SHOW COLLATION
mysql Information: 4 : 1: Resultset Opened: field(s) = 6, affected rows = -1, inserted id = -1
mysql Information: 5 : 1: Resultset Closed. Total rows=127, skipped rows=0, size (bytes)=4102
mysql Information: 6 : 1: Query Closed
mysql Information: 3 : 1: Query Opened: SET character_set_results=NULL
mysql Information: 4 : 1: Resultset Opened: field(s) = 0, affected rows = 0, inserted id = 0
mysql Information: 5 : 1: Resultset Closed. Total rows=0, skipped rows=0, size (bytes)=0
mysql Information: 6 : 1: Query Closed
mysql Information: 10 : 1: Set Database: world
mysql Information: 3 : 1: Query Opened: SELECT Name, HeadOfState FROM Country WHERE Continent='Oceania'
mysql Information: 4 : 1: Resultset Opened: field(s) = 2, affected rows = -1, inserted id = -1
American Samoa -- George W. Bush
Australia -- Elisabeth II
...
Wallis and Futuna -- Jacques Chirac
Vanuatu -- John Bani
United States Minor Outlying Islands -- George W. Bush
mysql Information: 5 : 1: Resultset Closed. Total rows=28, skipped rows=0, size (bytes)=788
mysql Information: 6 : 1: Query Closed
Done.
mysql Information: 2 : 1: Connection Closed

The first number displayed in the trace message corresponds to the MySQL event type:

EventОписание
1ConnectionOpened: connection string
2ConnectionClosed:
3QueryOpened: mysql server thread id, query text
4ResultOpened: field count, affected rows (-1 if select), inserted id (-1 if select)
5ResultClosed: total rows read, rows skipped, size of resultset in bytes
6QueryClosed:
7StatementPrepared: prepared sql, statement id
8StatementExecuted: statement id, mysql server thread id
9StatementClosed: statement id
10NonQuery: [varies]
11UsageAdvisorWarning: usage advisor flag. NoIndex = 1, BadIndex = 2, SkippedRows = 3, SkippedColumns = 4, FieldConversion = 5.
12Warning: level, code, message
13Error: error number, error message

The second number displayed in the trace message is the connection count.

Although this example uses the ConsoleTraceListener, any of the other standard listeners could have been used. Another possibility is to create a custom listener that uses the information passed using the TraceEvent method. For example, a custom trace listener could be created to perform active monitoring of the MySQL event messages, rather than simply writing these to an output device.

It is also possible to add listeners to the MySQL Trace Source at run time. This can be done with the following code:

MySqlTrace.Listeners.Add(new ConsoleTraceListener());

MySQL Connector/Net 6.3.2 introduced the ability to switch tracing on and off at run time. This can be achieved using the calls MySqlTrace.EnableQueryAnalyzer(string host, int postInterval) and MySqlTrace.DisableQueryAnalyzer(). The parameter host is the URL of the MySQL Enterprise Monitor server to monitor. The parameter postInterval is how often to post the data to MySQL Enterprise Monitor, in seconds.

21.2.5.16.2. Building Custom Listeners

To build custom listeners that work with the MySQL Connector/Net Trace Source, it is necessary to understand the key methods used, and the event data formats used.

The main method involved in passing trace messages is the TraceSource.TraceEvent method. This has the prototype:

public void TraceEvent(
    TraceEventType eventType,
    int id,
    string format,
    params Object[] args
)

This trace source method will process the list of attached listeners and call the listener's TraceListener.TraceEvent method. The prototype for the TraceListener.TraceEvent method is as follows:

public virtual void TraceEvent(
    TraceEventCache eventCache,
    string source,
    TraceEventType eventType,
    int id,
    string format,
    params Object[] args
)

The first three parameters are used in the standard as defined by Microsoft. The last three parameters contain MySQL-specific trace information. Each of these parameters is now discussed in more detail.

int id

This is a MySQL-specific identifier. It identifies the MySQL event type that has occurred, resulting in a trace message being generated. This value is defined by the MySqlTraceEventType public enum contained in the MySQL Connector/Net code:

public enum MySqlTraceEventType : int
{
    ConnectionOpened = 1,
    ConnectionClosed,
    QueryOpened,
    ResultOpened,
    ResultClosed,
    QueryClosed,
    StatementPrepared,
    StatementExecuted,
    StatementClosed,
    NonQuery,
    UsageAdvisorWarning,
    Warning,
    Error
}

The MySQL event type also determines the contents passed using the parameter params Object[] args. The nature of the args parameters are described in further detail in the following material.

string format

This is the format string that contains zero or more format items, which correspond to objects in the args array. This would be used by a listener such as ConsoleTraceListener to write a message to the output device.

params Object[] args

This is a list of objects that depends on the MySQL event type, id. However, the first parameter passed using this list is always the driver id. The driver id is a unique number that is incremented each time the connector is opened. This enables groups of queries on the same connection to be identified. The parameters that follow driver id depend of the MySQL event id, and are as follows:

MySQL-specific event typeArguments (params Object[] args)
ConnectionOpenedConnection string
ConnectionClosedNo additional parameters
QueryOpenedmysql server thread id, query text
ResultOpenedfield count, affected rows (-1 if select), inserted id (-1 if select)
ResultClosedtotal rows read, rows skipped, size of resultset in bytes
QueryClosedNo additional parameters
StatementPreparedprepared sql, statement id
StatementExecutedstatement id, mysql server thread id
StatementClosedstatement id
NonQueryVaries
UsageAdvisorWarningusage advisor flag. NoIndex = 1, BadIndex = 2, SkippedRows = 3, SkippedColumns = 4, FieldConversion = 5.
Warninglevel, code, message
Errorerror number, error message

This information will allow you to create custom trace listeners that can actively monitor the MySQL-specific events.

21.2.5.17. Using the Bulk Loader

MySQL Connector/Net features a bulk loader class that wraps the MySQL statement LOAD DATA INFILE. This gives MySQL Connector/Net the ability to load a data file from a local or remote host to the server. The class concerned is MySqlBulkLoader. This class has various methods, the main one being load to cause the specified file to be loaded to the server. Various parameters can be set to control how the data file is processed. This is achieved through setting various properties of the class. For example, the field separator used, such as comma or tab, can be specified, along with the record terminator, such as newline.

The following code shows a simple example of using the MySqlBulkLoader class. First an empty table needs to be created, in this case in the test database:

CREATE TABLE Career (
       Name VARCHAR(100) NOT NULL,
       Age INTEGER,
       Profession VARCHAR(200)
);

A simple tab-delimited data file is also created (it could use any other field delimiter such as comma):

Table Career in Test Database
Name	Age	Profession

Tony	47	Technical Writer
Ana	43	Nurse
Fred	21	IT Specialist
Simon	45	Hairy Biker

Note that with this test file the first three lines will need to be ignored, as they do not contain table data. This can be achieved using the NumberOfLinesToSkip property. This file can then be loaded and used to populate the Career table in the test database:

using System;
using System.Text;
using MySql.Data;
using MySql.Data.MySqlClient;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {

            string connStr = "server=localhost;user=root;database=test;port=3306;password=******;";
            MySqlConnection conn = new MySqlConnection(connStr);

            MySqlBulkLoader bl = new MySqlBulkLoader(conn);
            bl.TableName = "Career";
            bl.FieldTerminator = "\t";
            bl.LineTerminator = "\n";
            bl.FileName = "c:/career_data.txt";
            bl.NumberOfLinesToSkip = 3;

            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();

                // Upload data from file
                int count = bl.Load();
                Console.WriteLine(count + " lines uploaded.");

                string sql = "SELECT Name, Age, Profession FROM Career";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                MySqlDataReader rdr = cmd.ExecuteReader();

                while (rdr.Read())
                {
                    Console.WriteLine(rdr[0] + " -- " + rdr[1] + " -- " + rdr[2]);
                }

                rdr.Close();

                conn.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            Console.WriteLine("Done.");
        }
    }
}

Further information on LOAD DATA INFILE can be found in Section 12.2.6, “LOAD DATA INFILE Синтаксис”. Further information on MySqlBulkLoader can be found in the reference documentation that was included with your connector.

21.2.6. Connector/Net Connection String Options Reference

NameDefaultОписание
Allow Batch, AllowBatchtrueWhen 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 ';'.
Allow User Variables, AllowUserVariablesfalseSetting this to true indicates that the provider expects user variables in the SQL. This option was added in Connector/Net version 5.2.2.
Allow Zero Datetime, AllowZeroDateTimefalseIf set to True, MySqlDataReader.GetValue() returns a MySqlDateTime object for date or datetime columns that have disallowed values, such as zero datetime values, and a System.DateTime object for valid values. If set to False (the default setting) it will cause a System.DateTime object to be returned for all legal values and an exception to be thrown for disallowed values, such as zero datetime values.
Auto Enlist, AutoEnlisttrueIf AutoEnlist is set to true, which is the default, a connection opened using TransactionScope participates in this scope, it commits when the scope commits and rolls back if TransactionScope does not commit. However, this feature is considered security sensitive and therefore cannot be used in a medium trust environment.
BlobAsUTF8ExcludePatternnullA POSIX-style regular expression that matches the names of BLOB columns that do not contain UTF-8 character data. See Section 21.2.5.14, “Character Sets” for usage details.
BlobAsUTF8IncludePatternnullA POSIX-style regular expression that matches the names of BLOB columns containing UTF-8 character data. See Section 21.2.5.14, “Character Sets” for usage details.
Certificate File, CertificateFilenullThis option specifies the path to a certificate file in PKCS #12 format (.pfx). For an example of usage, see Section 21.2.4.7, “Tutorial: Using SSL with MySQL Connector/Net”. Was introduced with 6.2.1.
Certificate Password, CertificatePasswordnullSpecifies a password that is used in conjunction with a certificate specified using the option CertificateFile. For an example of usage, see Section 21.2.4.7, “Tutorial: Using SSL with MySQL Connector/Net”. Was introduced with 6.2.1.
Certificate Store Location, CertificateStoreLocationnullEnables you to access a certificate held in a personal store, rather than use a certificate file and password combination. For an example of usage, see Section 21.2.4.7, “Tutorial: Using SSL with MySQL Connector/Net”. Was introduced with 6.2.1.
Certificate Thumbprint, CertificateThumbprintnullSpecifies a certificate thumbprint to ensure correct identification of a certificate contained within a personal store. For an example of usage, see Section 21.2.4.7, “Tutorial: Using SSL with MySQL Connector/Net”. Was introduced with 6.2.1.
CharSet, Character Set, CharacterSet 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 result data.
Check Parameters, CheckParameterstrueIndicates if stored routine parameters should be checked against the server.
Connect Timeout, Connection Timeout, ConnectionTimeout15The length of time (in seconds) to wait for a connection to the server before terminating the attempt and generating an error.
Connection Reset, ConnectionResetfalseIf true, the connection state will be reset when it is retrieved from the pool. The default value of false avoids making an additional server round trip when obtaining a connection, but the connection state is not reset.
Convert Zero Datetime, ConvertZeroDateTimefalseTrue to have MySqlDataReader.GetValue() and MySqlDataReader.GetDateTime() return DateTime.MinValue for date or datetime columns that have disallowed values.
Default Command Timeout, DefaultCommandTimeout30Sets 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
Default Table Cache Age, DefaultTableCacheAge60Specifies how long a TableDirect result should be cached, in seconds.
Encrypt, UseSSLfalseFor 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. From version 6.2.1, this option is deprecated and is replaced by SSL Mode. The option still works if used. If this option is set to true, it is equivalent to SSL Mode = Preferred.
Exception Interceptors, ExceptionInterceptors The list of interceptors that can triage thrown MySqlException exceptions.
Functions Return String, FunctionsReturnStringfalseCauses the connector to return binary/varbinary values as strings, if they do not have a tablename in the metadata.
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 take care when using this option. In Unix environment with Mono, this can be a fully qualified path to a MySQL socket file. With this configuration, the Unix socket will be used instead of the 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 Prepare, IgnorePreparetrueWhen true, instructs the provider to ignore any calls to MySqlCommand.Prepare(). This option is provided to prevent issues with corruption of the statements when used with server-side prepared statements. If you 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.
Initial Catalog, DatabasemysqlThe case-sensitive name of the database to use initially.
Interactive, Interactive Session, InteractiveSessionfalseIf set to true, the client is interactive. An interactive client is one where the server variable CLIENT_INTERACTIVE is set. If an interactive client is set, the wait_timeout variable is set to the value of interactive_timeout. The client will then timeout after this period of inactivity. More details can be found in the server manual Section 5.1.3, “Server System Variables”.
Integrated Security, IntegratedSecurityfalseUse Windows authentication when connecting to server.
Keep Alive, Keepalive0For TCP connections, idle connection time measured in seconds, before the first keepalive packet is sent. A value of 0 indicates that keepalive is not used.
LoggingfalseWhen true, various pieces of information is output to any configured TraceListeners. See Section 21.2.5.16, “Using the MySQL Connector/Net Trace Source Object” for further details.
Old Guids, OldGuidsfalseThis option was introduced in Connector/Net 6.1.1. The backend representation of a GUID type was changed from BINARY(16) to CHAR(36). This was done to allow developers to use the server function UUID() to populate a GUID table - UUID() generates a 36-character string. Developers of older applications can add 'Old Guids=true' to the connection string to use a GUID of data type BINARY(16).
Old Синтаксис, OldSyntax, Use Old Синтаксис, UseOldSyntaxfalseThis option was deprecated in Connector/Net 5.2.2. All code should now be written using the '@' symbol as the parameter marker.
Password, pwd The password for the MySQL account being used.
Persist Security Info, PersistSecurityInfofalseWhen 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.
Pipe Name, Pipe, PipeNamemysqlWhen set to the name of a named pipe, the MySqlConnection will attempt to connect to MySQL on that named pipe. This setting only applies to the Windows platform.
Port3306The port MySQL is using to listen for connections. This value is ignored if Unix socket is used.
Procedure Cache Size, ProcedureCacheSize, procedure cache, procedurecache25Sets the size of the stored procedure cache. By default, Connector/Net stores the metadata (input/output data types) 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.
Protocol, Connection Protocol, ConnectionProtocolsocketSpecifies 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.
ReplicationfalseIndicates if this connection is to use replicated servers.
Respect Binary Flags, RespectBinaryFlagstrueSetting this option to false means that Connector/Net ignores a column's binary flags as set by the server. This option was added in Connector/Net version 5.1.3.
Shared Memory Name, SharedMemoryNameMYSQLThe name of the shared memory object to use for communication if the connection protocol is set to memory.
Sql Server Mode, sqlservermodefalseAllow SQL Server syntax. When set to true, enables Connector/Net to support square brackets around symbols instead of backticks. This enables Visual Studio wizards that bracket symbols with [] to work with Connector/Net. This option incurs a performance hit, so should only be used if necessary. This option was added in version 6.3.1.
SSL Mode, SslModeNoneThis option has the following values:
  • None - do not use SSL.

  • Preferred - use SSL if the server supports it, but allow connection in all cases.

  • Required - Always use SSL. Deny connection if server does not support SSL.

  • VerifyCA - Always use SSL. Validate the CA but tolerate name mismatch.

  • VerifyFull - Always use SSL. Fail if the host name is not correct.

This option was introduced in MySQL Connector/Net 6.2.1.

Table Cache, tablecachefalseEnables or disables caching of TableDirect commands. A value of yes enables the cache while no disables it.
TreatBlobsAsUTF8false 
Treat Tiny As Boolean, TreatTinyAsBooleantrueSetting this value to false indicates that TINYINT(1) will be treated as an INT. See Section 10.1.1, “Numeric Type Overview” for a further explanation of the TINYINT and BOOL data types.
Use Affected Rows, UseAffectedRowsfalseWhen true the connection will report changed rows instead of found rows. This option was added in Connector/Net version 5.2.6.
Use Procedure Bodies, UseProcedureBodies, procedure bodiestrueWhen set to true, the default value, MySQL Connector/Net expects the body of the procedure to be viewable. This enables it to determine the parameter types and order. Set the option to false when the user connecting to the database does not have the SELECT privileges for the mysql.proc (stored procedures) table, or cannot view INFORMATION_SCHEMA.ROUTINES. In this case, MySQL Connector/Net cannot determine the types and order of the parameters, and must be alerted to this fact by setting this option to false. When set to false, MySQL Connector/Net does not rely on this information being available when the procedure is called. Because MySQL Connector/Net will not be able to determine this information, explicitly set the types of all the parameters before the call and add the parameters to the command in the same order as they appear in the procedure definition. This option was added in MySQL Connector/Net 5.0.4 and MySQL Connector/Net 1.0.10.
User Id, UserID, Username, Uid, User name, User The MySQL login account being used.
Use Compression, UseCompressionfalse

Setting this option to true enables compression of packets exchanged between the client and the server. This exchange is defined by the MySQL client/server protocol.

Compression is used if both client and server support ZLIB compression, and the client has requested compression using this option.

A compressed packet header is: packet length (3 bytes), packet number (1 byte), and Uncompressed Packet Length (3 bytes). The Uncompressed Packet Length is the number of bytes in the original, uncompressed packet. If this is zero, the data in this packet has not been compressed. When the compression protocol is in use, either the client or the server may compress packets. However, compression will not occur if the compressed length is greater than the original length. Thus, some packets will contain compressed data while other packets will not.

Use Usage Advisor, Usage Advisor, UseUsageAdvisorfalseLogs inefficient database operations.
Use Performance Monitor, UsePerformanceMonitor, userperfmon, perfmonfalseIndicates that performance counters should be updated during execution.

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.

NameDefaultОписание
Cache Server Properties, CacheServerPropertiesfalseSpecifies whether server variables should be updated when a pooled connection is returned. Turning this on will yield faster opens but will also not catch any server changes made by other connections.
Command Interceptors, CommandInterceptors The list of interceptors that can intercept SQL command operations.
Connection Lifetime, ConnectionLifeTime0When 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.
Minimum Pool Size, Min Pool Size, MinimumPoolSize0The 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.

21.2.7. Connector/Net API Reference

This section of the manual contains a complete reference to the Connector/Net ADO.NET component, automatically generated from the embedded documentation.

21.2.7.1. MySql.Data.MySqlClient

Namespace hierarchy

Classes

ClassОписание
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

DelegateОписание
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

EnumerationОписание
MySqlDbTypeSpecifies MySQL-specific data type of a field, property, for use in a MySqlParameter.
MySqlErrorCode 
21.2.7.1.1. MySql.Data.MySqlClientHierarchy

See Also

MySql.Data.MySqlClient Namespace

21.2.7.1.2. 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

21.2.7.1.2.1. 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 IContainer that contains the Component.
IsPrepared 
Parameters 
Site (inherited from Component)Gets or sets the ISite of 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 Object is equal to the current Object.
ExecuteNonQuery 
ExecuteReaderOverloaded.
ExecuteScalar 
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is 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 Type of 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 String containing 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 Disposed event on the component.

See Also

MySqlCommand Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1. 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

21.2.7.1.2.1.1.1. 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

21.2.7.1.2.1.1.2. 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

21.2.7.1.2.1.1.3. 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

21.2.7.1.2.1.1.3.1. 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

21.2.7.1.2.1.1.3.1.1. 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 IContainer that 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 ISite of 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 Object is equal to the current Object.
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is 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 Type of 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 String containing 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 Disposed event on the component.
InfoMessage 
StateChange 

See Also

MySqlConnection Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.1. 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

21.2.7.1.2.1.1.3.1.1.1.1. 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

21.2.7.1.2.1.1.3.1.1.1.2. 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

21.2.7.1.2.1.1.3.1.1.2. 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

21.2.7.1.2.1.1.3.1.1.3. 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

21.2.7.1.2.1.1.3.1.1.4. 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

21.2.7.1.2.1.1.3.1.1.5. 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

21.2.7.1.2.1.1.3.1.1.6. 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

21.2.7.1.2.1.1.3.1.1.7. 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

21.2.7.1.2.1.1.3.1.1.8. 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

21.2.7.1.2.1.1.3.1.1.9. 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

21.2.7.1.2.1.1.3.1.1.10. BeginTransaction Method

Overload List

See Also

MySqlConnection Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.10.1. 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

21.2.7.1.2.1.1.3.1.1.10.1.1. 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 (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

MySqlTransaction Members, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.10.1.1.1. 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 IsolationLevel for this transaction.

Public Instance Methods

Commit 
Equals (inherited from Object)Determines whether the specified Object is equal to the current Object.
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is suitable for use in hashing algorithms and data structures like a hash table.
GetType (inherited from Object)Gets the Type of the current instance.
Rollback 
ToString (inherited from Object)Returns a String that represents the current Object.

See Also

MySqlTransaction Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.10.1.1.1.1. 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

21.2.7.1.2.1.1.3.1.1.10.1.1.1.2. IsolationLevel Property

Specifies the IsolationLevel for 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

21.2.7.1.2.1.1.3.1.1.10.1.1.1.3. 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

21.2.7.1.2.1.1.3.1.1.10.1.1.1.4. 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

21.2.7.1.2.1.1.3.1.1.10.2. 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

21.2.7.1.2.1.1.3.1.1.11. 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

21.2.7.1.2.1.1.3.1.1.12. 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

21.2.7.1.2.1.1.3.1.1.13. MySqlConnection.CreateCommand Method

Syntax: Visual Basic

Public Function CreateCommand() As MySqlCommand

Syntax: C#

public MySqlCommand CreateCommand();

See Also

MySqlConnection Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.14. 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

21.2.7.1.2.1.1.3.1.1.15. 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

21.2.7.1.2.1.1.3.1.1.16. 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

21.2.7.1.2.1.1.3.1.1.16.1. 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

21.2.7.1.2.1.1.3.1.1.16.1.1. 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 (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

MySqlInfoMessageEventArgs Members, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.16.1.1.1. MySqlInfoMessageEventArgs Members

MySqlInfoMessageEventArgs overview

Public Instance Constructors

Public Instance Fields

Public Instance Methods

Equals (inherited from Object)Determines whether the specified Object is equal to the current Object.
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is suitable for use in hashing algorithms and data structures like a hash table.
GetType (inherited from Object)Gets the Type of the current instance.
ToString (inherited from Object)Returns a String that represents the current Object.

Protected Instance Methods

Finalize (inherited from Object)Allows an Object to attempt to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection.
MemberwiseClone (inherited from Object)Creates a shallow copy of the current Object.

See Also

MySqlInfoMessageEventArgs Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.16.1.1.1.1. 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

21.2.7.1.2.1.1.3.1.1.16.1.1.1.2. MySqlInfoMessageEventArgs.errors Field

Syntax: Visual Basic

Public errors As MySqlError()

Syntax: C#

public MySqlError[] errors;

See Also

MySqlInfoMessageEventArgs Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.16.1.1.1.2.1. 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

21.2.7.1.2.1.1.3.1.1.16.1.1.1.2.1.1. 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 Object is equal to the current Object.
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is suitable for use in hashing algorithms and data structures like a hash table.
GetType (inherited from Object)Gets the Type of the current instance.
ToString (inherited from Object)Returns a String that represents the current Object.

Protected Instance Methods

Finalize (inherited from Object)Allows an Object to attempt to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection.
MemberwiseClone (inherited from Object)Creates a shallow copy of the current Object.

See Also

MySqlError Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.1.3.1.1.16.1.1.1.2.1.1.1. 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

21.2.7.1.2.1.1.3.1.1.16.1.1.1.2.1.1.2. 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

21.2.7.1.2.1.1.3.1.1.16.1.1.1.2.1.1.3. 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

21.2.7.1.2.1.1.3.1.1.16.1.1.1.2.1.1.4. 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

21.2.7.1.2.1.1.3.1.1.17. 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

21.2.7.1.2.1.1.4. 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

21.2.7.1.2.1.2. 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

21.2.7.1.2.1.3. 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

21.2.7.1.2.1.4. 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

21.2.7.1.2.1.5. 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

21.2.7.1.2.1.6. 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

21.2.7.1.2.1.7. 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

21.2.7.1.2.1.7.1. 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

21.2.7.1.2.1.7.1.1. 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 Object is equal to the current Object.
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is 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 Type of 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 String that represents the current Object.

See Also

MySqlParameterCollection Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.7.1.1.1. 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

21.2.7.1.2.1.7.1.1.2. 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

21.2.7.1.2.1.7.1.1.3. 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

21.2.7.1.2.1.7.1.1.3.1. 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

21.2.7.1.2.1.7.1.1.3.1.1. MySqlParameter Members

MySqlParameter overview

Public Instance Constructors

MySqlParameterOverloaded. Initializes a new instance of the MySqlParameter class.

Public Instance Properties

DbTypeGets or sets the DbType of 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 DataRowVersion to 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 Object is equal to the current Object.
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is 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 Type of 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

21.2.7.1.2.1.7.1.1.3.1.1.1. 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 DataRowVersion to 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

21.2.7.1.2.1.7.1.1.3.1.1.1.1. 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

21.2.7.1.2.1.7.1.1.3.1.1.1.2. 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

21.2.7.1.2.1.7.1.1.3.1.1.1.2.1. 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 NameОписание
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

21.2.7.1.2.1.7.1.1.3.1.1.1.3. 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

21.2.7.1.2.1.7.1.1.3.1.1.1.4. 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 DataRowVersion to 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 Object that is the value of the MySqlParameter.

Exceptions

Exception TypeCondition
ArgumentException 

See Also

MySqlParameter Class, MySql.Data.MySqlClient Namespace, MySqlParameter Constructor Overload List

21.2.7.1.2.1.7.1.1.3.1.1.1.4.1. 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

21.2.7.1.2.1.7.1.1.3.1.1.1.5. 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

21.2.7.1.2.1.7.1.1.3.1.1.1.6. 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 Object that is the value of the MySqlParameter.

See Also

MySqlParameter Class, MySql.Data.MySqlClient Namespace, MySqlParameter Constructor Overload List

21.2.7.1.2.1.7.1.1.3.1.1.2. DbType Property

Gets or sets the DbType of 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

21.2.7.1.2.1.7.1.1.3.1.1.3. 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

21.2.7.1.2.1.7.1.1.3.1.1.4. 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

21.2.7.1.2.1.7.1.1.3.1.1.5. 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

21.2.7.1.2.1.7.1.1.3.1.1.6. 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

21.2.7.1.2.1.7.1.1.3.1.1.7. 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

21.2.7.1.2.1.7.1.1.3.1.1.8. 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

21.2.7.1.2.1.7.1.1.3.1.1.9. 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

21.2.7.1.2.1.7.1.1.3.1.1.10. 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

21.2.7.1.2.1.7.1.1.3.1.1.11. 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

21.2.7.1.2.1.7.1.1.3.1.1.12. SourceVersion Property

Gets or sets the DataRowVersion to 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

21.2.7.1.2.1.7.1.1.3.1.1.13. 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

21.2.7.1.2.1.7.1.1.3.2. 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

21.2.7.1.2.1.7.1.1.3.3. 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

21.2.7.1.2.1.7.1.1.4. 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

21.2.7.1.2.1.7.1.1.4.1. 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

21.2.7.1.2.1.7.1.1.4.2. 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

21.2.7.1.2.1.7.1.1.4.3. 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

21.2.7.1.2.1.7.1.1.4.4. 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

21.2.7.1.2.1.7.1.1.4.5. 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

21.2.7.1.2.1.7.1.1.4.6. 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

21.2.7.1.2.1.7.1.1.5. 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

21.2.7.1.2.1.7.1.1.6. 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

21.2.7.1.2.1.7.1.1.6.1. 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

21.2.7.1.2.1.7.1.1.6.2. 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

21.2.7.1.2.1.7.1.1.7. 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

Implements

ICollection.CopyTo

See Also

MySqlParameterCollection Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.7.1.1.8. 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

21.2.7.1.2.1.7.1.1.8.1. 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

21.2.7.1.2.1.7.1.1.8.2. 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

21.2.7.1.2.1.7.1.1.9. 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

Implements

IList.Insert

See Also

MySqlParameterCollection Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.7.1.1.10. 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

21.2.7.1.2.1.7.1.1.11. 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

21.2.7.1.2.1.7.1.1.11.1. 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

21.2.7.1.2.1.7.1.1.11.2. 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

21.2.7.1.2.1.8. 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

21.2.7.1.2.1.9. 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

21.2.7.1.2.1.10. 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

21.2.7.1.2.1.11. 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

21.2.7.1.2.1.12. 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

21.2.7.1.2.1.13. ExecuteReader Method

Overload List

See Also

MySqlCommand Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.13.1. 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

21.2.7.1.2.1.13.1.1. 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

21.2.7.1.2.1.13.1.1.1. 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 Object is 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. GetHashCode is 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 Type of 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 String that represents the current Object.

See Also

MySqlDataReader Class, MySql.Data.MySqlClient Namespace

21.2.7.1.2.1.13.1.1.1.1. 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

21.2.7.1.2.1.13.1.1.1.2. 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

21.2.7.1.2.1.13.1.1.1.3. 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

21.2.7.1.2.1.13.1.1.1.4. 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

21.2.7.1.2.1.13.1.1.1.5. 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

21.2.7.1.2.1.13.1.1.1.5.1. 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

21.2.7.1.2.1.13.1.1.1.5.2. 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

21.2.7.1.2.1.13.1.1.1.6. 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

21.2.7.1.2.1.13.1.1.1.7. 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

21.2.7.1.2.1.13.1.1.1.8. 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

21.2.7.1.2.1.13.1.1.1.9. 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

21.2.7.1.2.1.13.1.1.1.10. 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

21.2.7.1.2.1.13.1.1.1.11. 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

21.2.7.1.2.1.13.1.1.1.12. 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

21.2.7.1.2.1.13.1.1.1.13. 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

21.2.7.1.2.1.13.1.1.1.14. 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

21.2.7.1.2.1.13.1.1.1.15. 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

21.2.7.1.2.1.13.1.1.1.16. 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

21.2.7.1.2.1.13.1.1.1.17. 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

21.2.7.1.2.1.13.1.1.1.18. 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

21.2.7.1.2.1.13.1.1.1.19. 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

21.2.7.1.2.1.13.1.1.1.20. 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

21.2.7.1.2.1.13.1.1.1.21. 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

21.2.7.1.2.1.13.1.1.1.22. 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

21.2.7.1.2.1.13.1.1.1.23. 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

21.2.7.1.2.1.13.1.1.1.24. 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

21.2.7.1.2.1.13.1.1.1.25. 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

21.2.7.1.2.1.13.1.1.1.26. 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

21.2.7.1.2.1.13.1.1.1.27. 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

21.2.7.1.2.1.13.1.1.1.28. 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

21.2.7.1.2.1.13.1.1.1.29. 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

21.2.7.1.2.1.13.1.1.1.30. 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

21.2.7.1.2.1.13.1.1.1.31. 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

21.2.7.1.2.1.13.1.1.1.32. 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

21.2.7.1.2.1.13.1.1.1.33. 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

21.2.7.1.2.1.13.1.1.1.34. 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

21.2.7.1.2.1.13.1.1.1.35. 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

21.2.7.1.2.1.13.1.1.1.36. 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

21.2.7.1.2.1.13.2. 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

21.2.7.1.2.1.14. 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

21.2.7.1.2.1.15. 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

21.2.7.1.3. 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 (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

MySqlCommandBuilder Members, MySql.Data.MySqlClient Namespace

21.2.7.1.3.1. 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 IContainer that contains the Component.
DataAdapter 
QuotePrefix 
QuoteSuffix 
Site (inherited from Component)Gets or sets the ISite of 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 Object is equal to the current Object.
GetDeleteCommand 
GetHashCode (inherited from Object)Serves as a hash function for a particular type. GetHashCode is 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 Type of 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 String containing 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 Disposed event on the component.

See Also

MySqlCommandBuilder Class, MySql.Data.MySqlClient Namespace

21.2.7.1.3.1.1. DeriveParameters Method