To run MySQL on Windows, you need the following:

To install MySQL on Windows using a binary distribution, follow this procedure:

Important note: Early alpha Windows distributions for MySQL 4.1 do not contain an installer program. A 4.1 distribution is a Zip file that you just unzip in the location where you want to install MySQL. For example, to install mysql-4.1.1-alpha-win.zip as C:\mysql, unzip the distribution file on the C: drive, then rename the resulting mysql-4.1.1-alpha directory to mysql.

If you are upgrading to MySQL 4.1 from an earlier version, you will want to preserve your existing data directory that contains the grant tables in the mysql database and your own databases. Before installing 4.1, stop the server if it is running, and save your data directory to another location. Then either rename the existing C:\mysql directory or remove it. Install 4.1 as described in the preceding paragraph, and then replace its data directory with your old data directory. This will avoid the loss of your current databases. Start the new server and update the grant tables. See the section called “Upgrading the Grant Tables”.

Please see the section called “Troubleshooting a MySQL Installation Under Windows” if you encounter difficulties during installation.

If you need to specify startup options when you run the server, you can indicate them on the command line or place them in an option file. For options that will be used every time the server starts, you will find it most convenient to use an option file to specify your MySQL configuration. This is true particularly under the following circumstances:

On Windows, the MySQL installer places the data directory directly under the directory where you install MySQL. If you would like to use a data directory in a different location, you should copy the entire contents of the data directory to the new location. For example, by default, the installer places MySQL in C:\mysql and the data directory in C:\mysql\data. If you want to use a data directory of E:\mydata, you must do two things:

When the MySQL server starts on Windows, it looks for options in two files: the my.ini file in the Windows directory, and the C:\my.cnf file. The Windows directory typically is named something like C:\WINDOWS or C:\WinNT. You can determine its exact location from the value of the WINDIR environment variable using the following command:

C:\> echo %WINDIR%

MySQL looks for options first in the my.ini file, then in the my.cnf file. However, to avoid confusion, it's best if you use only one file. If your PC uses a boot loader where the C: drive isn't the boot drive, your only option is to use the my.ini file. Whichever option file you use, it must be a plain text file.

An option file can be created and modified with any text editor, such as the Notepad program. For example, if MySQL is installed at E:\mysql and the data directory is located at E:\mydata\data, you can create the option file and set up a [mysqld] section to specify values for the basedir and datadir parameters:

[mysqld]
# set basedir to your installation path
basedir=E:/mysql
# set datadir to the location of your data directory
datadir=E:/mydata/data

Note that Windows pathnames are specified in option files using forward slashes rather than backslashes. If you do use backslashes, you must double them.

Another way to manage an option file is to use the WinMySQLAdmin tool. You can find WinMySQLAdmin in the bin directory of your MySQL installation, as well as a help file containing instructions for using it. WinMySQLAdmin has the capability of editing your option file, but note these points:

Now you are ready to start the server.

Starting with MySQL 3.23.38, the Windows distribution includes both the normal and the MySQL-Max server binaries.

Up through the early releases of MySQL 4.1, the servers included in Windows distributions are named like this:

We have found that the server with the most generic name (mysqld) is the one that many users are likely to choose by default. However, that is also the server that results in the highest memory and CPU use due to the inclusion of full debugging support. The server named mysqld-opt is a better general-use server choice to make instead if you don't need debugging suport and don't want the maximal feature set offered by the -max servers or named pipe support offered by the -nt servers.

To make it less likely that the debugging server would be chosen inadvertantly, some name changes were made from MySQL 4.1.2 to 4.1.4: mysqld has been renamed to mysqld-debug and mysqld-opt has been renamed to mysqld. Thus, the server that includes debugging support indicates that in its name, and the server named mysqld is an efficient default choice. The other servers still have their same names. The resulting servers are named like this:

The name changes were not both instituted at the same time. If you have MySQL 4.1.2 or 4.1.3, it might be that you have a server named mysqld-debug but not one named mysqld. In this case, you should have have a server mysqld-opt, which you should choose as your default server unless you need maximal features, named pipes, or debugging support.

All of the preceding binaries are optimized for modern Intel processors, but should work on any Intel i386-class or higher processor.

MySQL supports TCP/IP on all Windows platforms. The mysqld-nt and mysql-max-nt servers support named pipes on NT, 2000, and XP. However, the default is to use TCP/IP regardless of the platform. (Named pipes are slower than TCP/IP in many Windows configurations.) Named pipe use is subject to these conditions:

Note: Most of the examples in the following sections use mysqld as the server name. If you choose to use a different server, such as mysqld-opt, make the appropriate substitutions in the commands that are shown in the examples. One good reason to choose a different server is that because mysqld contains full debugging support, it uses more memory and runs slower than the other Windows servers.

On Windows 95, 98, or Me, MySQL clients always connect to the server using TCP/IP. (This will allow any machine on your network to connect to your MySQL server.) Because of this, you must make sure that TCP/IP support is installed on your machine before starting MySQL. You can find TCP/IP on your Windows CD-ROM.

Note that if you are using an old Windows 95 release (for example, OSR2), it's likely that you have an old Winsock package; MySQL requires Winsock 2! You can get the newest Winsock from http://www.microsoft.com/. Windows 98 has the new Winsock 2 library, so it is unnecessary to update the library.

On NT-based systems such as Windows NT, 2000, or XP, clients have two options. They can use TCP/IP, or they can use a named pipe if the server supports named pipe connections.

In MySQL 4.1 and up, Windows servers also support shared-memory connections if started with the --shared-memory option. Clients can connect this way by using the --protocol=memory option.

For information about which server binary to run, see the section called “Selecting a Windows Server”.

This section gives a general overview of starting the MySQL server. The following sections provide more specific information for particular versions of Windows.

The examples in these sections assume that MySQL is installed under the default location of C:\mysql. Adjust the pathnames shown in the examples if you have MySQL installed in a different location.

Testing is best done from a command prompt in a console window (a “DOS window”). This way you can have the server display status messages in the window where they are easy to see. If something is wrong with your configuration, these messages will make it easier for you to identify and fix any problems.

To start the server, enter this command:

C:\> C:\mysql\bin\mysqld --console

For servers that include InnoDB support, you should see the following messages as the server starts:

InnoDB: The first specified datafile c:\ibdata\ibdata1 did not exist:
InnoDB: a new database to be created!
InnoDB: Setting file c:\ibdata\ibdata1 size to 209715200
InnoDB: Database physically writes the file full: wait...
InnoDB: Log file c:\iblogs\ib_logfile0 did not exist: new to be created
InnoDB: Setting log file c:\iblogs\ib_logfile0 size to 31457280
InnoDB: Log file c:\iblogs\ib_logfile1 did not exist: new to be created
InnoDB: Setting log file c:\iblogs\ib_logfile1 size to 31457280
InnoDB: Log file c:\iblogs\ib_logfile2 did not exist: new to be created
InnoDB: Setting log file c:\iblogs\ib_logfile2 size to 31457280
InnoDB: Doublewrite buffer not found: creating new
InnoDB: Doublewrite buffer created
InnoDB: creating foreign key constraint system tables
InnoDB: foreign key constraint system tables created
011024 10:58:25  InnoDB: Started

When the server finishes its startup sequence, you should see something like this, which indicates that the server is ready to service client connections:

mysqld: ready for connections
Version: '4.0.14-log'  socket: ''  port: 3306

The server will continue to write to the console any further diagnostic output it produces. You can open a new console window in which to run client programs.

If you omit the --console option, the server writes diagnostic output to the error log in the data directory (C:\mysql\data by default). The error log is the file with the .err extension.

Note: The accounts that are listed in the MySQL grant tables initially have no passwords. After starting the server, you should set up passwords for them using the instructions in the section called “Post-Installation Setup and Testing”.

The MySQL server can be started manually from the command line. This can be done on any version of Windows.

To start the mysqld server from the command line, you should start a console window (a “DOS window”) and enter this command:

C:\> C:\mysql\bin\mysqld

On non-NT versions of Windows, this will start mysqld in the background. That is, after the server starts, you should see another command prompt. If you start the server this way on Windows NT, 2000, or XP, the server will run in the foreground and no command prompt will appear until the server exits. Because of this, you should open another console window to run client programs while the server is running.

You can stop the MySQL server by executing this command:

C:\> C:\mysql\bin\mysqladmin -u root shutdown

This invokes the MySQL administrative utility mysqladmin to connect to the server and tell it to shut down. The command connects as root, which is the default administrative account in the MySQL grant system. Note that users in the MySQL grant system are wholly independent from any login users under Windows.

If mysqld doesn't start, check the error log to see whether the server wrote any messages there to indicate the cause of the problem. The error log is located in the C:\mysql\data directory. It is the file with a suffix of .err. You can also try to start the server as mysqld --console; in this case, you may get some useful information on the screen that may help solve the problem.

The last option is to start mysqld with --standalone --debug. In this case, mysqld will write a log file C:\mysqld.trace that should contain the reason why mysqld doesn't start. See the section called “Creating Trace Files”.

Use mysqld --help to display all the options that mysqld understands!

On the NT family (Windows NT, 2000, or XP), the recommended way to run MySQL is to install it as a Windows service. Then Windows starts and stops the MySQL server automatically when Windows starts and stops. A server installed as a service can also be controlled from the command line using NET commands, or with the graphical Services utility.

The Services utility (the Windows Service Control Manager) can be found in the Windows Control Panel (under Administrative Tools on Windows 2000 or XP). It is advisable to close the Services utility while performing server installation or removal operations from this command line. This prevents some odd errors.

To get MySQL to work with TCP/IP on Windows NT 4, you must install service pack 3 (or newer).

Before installing MySQL as a Windows service, you should first stop the current server if it is running by using the following command:

C:\> C:\mysql\bin\mysqladmin -u root shutdown

This invokes the MySQL administrative utility mysqladmin to connect to the server and tell it to shut down. The command connects as root, which is the default administrative account in the MySQL grant system. Note that users in the MySQL grant system are wholly independent from any login users under Windows.

Now install the server as a service:

C:\> mysqld --install

If you have problems installing mysqld as a service using just the server name, try installing it using its full pathname:

C:\> C:\mysql\bin\mysqld --install

As of MySQL 4.0.2, you can specify a specific service name after the --install option. As of MySQL 4.0.3, you can in addition specify a --defaults-file option after the service name to indicate where the server should obtain options when it starts. The rules that determine the service name and option files the server uses are as follows:

Note: Prior to MySQL 4.0.17, a server installed as a Windows service has problems starting if its pathname or the service name contains spaces. For this reason, avoid installing MySQL in a directory such as C:\Program Files or using a service name containing spaces.

In the usual case that you install the server with --install but no service name, the server is installed with a service name of MySQL.

As a more complex example, consider the following command:

C:\> C:\mysql\bin\mysqld --install mysql --defaults-file=C:\my-opts.cnf

Here, a service name is given after the --install option. If no --defaults-file option had been given, this command would have the effect of causing the server to read the [mysql] group from the standard option files. (This would be a bad idea, because that option group is for use by the mysql client program.) However, because the --defaults-file option is present, the server reads options only from the named file, and only from the [mysqld] option group.

You can also specify options as “Start parameters” in the Windows Services utility before you start the MySQL service.

Once a MySQL server is installed as a service, Windows will start the service automatically whenever Windows starts. The service also can be started immediately from the Services utility, or by using the command NET START MySQL. The NET command is not case sensitive.

When run as a service, mysqld has no access to a console window, so no messages can be seen there. If mysqld doesn't start, check the error log to see whether the server wrote any messages there to indicate the cause of the problem. The error log is located in the C:\mysql\data directory. It is the file with a suffix of .err.

When mysqld is running as a service, it can be stopped by using the Services utility, the command NET STOP MySQL, or the command mysqladmin shutdown. If the service is running when Windows shuts down, Windows will stop the server automatically.

From MySQL 3.23.44 on, you have the choice of installing the server as a Manual service if you don't wish the service to be started automatically during the boot process. To do this, use the --install-manual option rather than the --install option:

C:\> C:\mysql\bin\mysqld --install-manual

To remove a server that is installed as a service, first stop it if it is running. Then use the --remove option to remove it:

C:\> C:\mysql\bin\mysqld --remove

For MySQL versions older than 3.23.49, one problem with automatic MySQL service shutdown is that Windows waited only for a few seconds for the shutdown to complete, then killed the database server process if the time limit was exceeded. This had the potential to cause problems. (For example, the InnoDB storage engine had to perform crash recovery at the next startup.) Starting from MySQL 3.23.49, Windows waits longer for the MySQL server shutdown to complete. If you notice this still is not enough for your installation, it is safest not to run the MySQL server as a service. Instead, start it from the command-line prompt, and stop it with mysqladmin shutdown.

This change to tell Windows to wait longer when stopping the MySQL server works for Windows 2000 and XP. It does not work for Windows NT, where Windows waits only 20 seconds for a service to shut down, and after that kills the service process. You can increase this default by opening the Registry Editor \winnt\system32\regedt32.exe and editing the value of WaitToKillServiceTimeout at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control in the Registry tree. Specify the new larger value in milliseconds. For example, the value 120000 tells Windows NT to wait up to 120 seconds.

If you don't want to start mysqld as a service, you can start it from the command line. For instructions, see the section called “Starting MySQL from the Windows Command Line”.

Please see the section called “Troubleshooting a MySQL Installation Under Windows” if you encounter difficulties during installation.

When installing and running MySQL for the first time, you may encounter certain errors that prevent the MySQL server from starting. The purpose of this section is to help you diagnose and correct some of these errors.

Your first resource when troubleshooting server issues is the error log. The MySQL server uses the error log to record information relevant to the error that is preventing the server from starting. The error log is located in the data directory specified in your my.ini file. The default data directory location is C:\mysql\data. See the section called “The Error Log”.

Another source of information regarding possible errors is the console messages displayed when the MySQL service is starting. Use the NET START mysql command from the command line after installing mysqld as a service to see any error messages regarding the starting of the MySQL server as a service. See the section called “Starting MySQL as a Windows Service”.

The following are examples of some of the more common error messages you may encounter when installing MySQL and starting the server for the first time:

System error 1067 has occurred.
Fatal error: Can't open privilege tables: Table 'mysql.host' doesn't exist

These messages occur when the MySQL server cannot find the mysql privileges database or other critical files. This error is often encountered when the MySQL base or data directories are installed in different locations than the default locations (C:\mysql and C:\mysql\data, respectively).

If you have installed MySQL to a directory other than C:\mysql you will need to ensure that the MySQL server is aware of this through the use of a configuration (my.ini) file. The my.ini file needs to be located in your Windows directory, typically located at C:\WinNT or C:\WINDOWS. You can determine its exact location from the value of the WINDIR environment variable by issuing the following command from the command prompt:

C:\> echo %WINDIR%

An option file can be created and modified with any text editor, such as the Notepad program. For example, if MySQL is installed at E:\mysql and the data directory is located at D:\MySQLdata, you can create the option file and set up a [mysqld] section to specify values for the basedir and datadir parameters:

[mysqld]
# set basedir to your installation path
basedir=E:/mysql
# set datadir to the location of your data directory
datadir=D:/MySQLdata

Note that Windows pathnames are specified in option files using forward slashes rather than backslashes. If you do use backslashes, you must double them:

[mysqld]
# set basedir to your installation path
basedir=C:\\Program Files\\mysql
# set datadir to the location of your data directory
datadir=D:\\MySQLdata

See the section called “Preparing the Windows MySQL Environment”.

You can test whether the MySQL server is working by executing any of the following commands:

C:\> C:\mysql\bin\mysqlshow
C:\> C:\mysql\bin\mysqlshow -u root mysql
C:\> C:\mysql\bin\mysqladmin version status proc
C:\> C:\mysql\bin\mysql test

If mysqld is slow to respond to TCP/IP connections from client programs on Windows 9x/Me, there is probably a problem with your DNS. In this case, start mysqld with the --skip-name-resolve option and use only localhost and IP numbers in the Host column of the MySQL grant tables.

You can force a MySQL client to use a named pipe connection rather than TCP/IP by specifying the --pipe option or by specifying . (period) as the host name. Use the --socket option to specify the name of the pipe. As of MySQL 4.1, you should use the --protocol=PIPE option.

There are two versions of the MySQL command-line tool:

If you want to use mysqlc, you must have a copy of the cygwinb19.dll library installed somewhere that mysqlc can find it. Current distributions of MySQL include this library in the same directory as mysqlc (the bin directory under the base directory of your MySQL installation). If your distribution does not have the cygwinb19.dll library in the bin directory, look for it in the lib directory and copy it to your Windows system directory (\Windows\system or a similar place).

MySQL for Windows has by now proven itself to be very stable. The Windows version of MySQL has the same features as the corresponding Unix version, with the following exceptions:

Here are some open issues for anyone who might want to help us improve MySQL on Windows: