After MySQL is installed, the data directory must be initialized,
including the tables in the
For some MySQL installation methods, data directory initialization is automatic, as described in Postinstallation Setup and Testing.
For other installation methods, you must initialize the data directory manually. These include installation from generic binary and source distributions on Unix and Unix-like systems, and installation from a ZIP Archive package on Windows.
This section describes how to initialize the data directory manually for MySQL installation methods for which data directory initialization is not automatic. For some suggested commands that enable testing whether the server is accessible and working properly, see Testing the Server.
In the examples shown here, the server is intended to run under
the user ID of the
mysql login account. This
assumes that such an account exists. Either create the account if
it does not exist (see
Create a mysql User and Group), or
substitute the name of a different existing login account that you
plan to use for running the server.
Change location to the top-level directory of your MySQL installation, which is typically
/usr/local/mysql(adjust the path name for your system as necessary):
You will find several files and subdirectories inside the directory, including the
scriptssubdirectories, which contain the server as well as client and utility programs.
Initialize the data directory, including the
mysqldatabase containing the initial MySQL grant tables that determine how users are permitted to connect to the server. For example:
Typically, data directory initialization need be done only after you first install MySQL. (For upgrades to an existing installation, perform the upgrade procedure instead; see Upgrading MySQL.) However, the command that initializes the data directory does not overwrite any existing privilege tables, so it is safe to run in any circumstances.
It is important to make sure that the database directories and files are owned by the
mysqllogin account so that the server has read and write access to them when you run it later. To ensure this if you run mysql_install_db as
root, include the
--useroption as shown.
The mysql_install_db command initializes the server's data directory. Under the data directory, it creates directories for the
mysqldatabase that holds the grant tables and the
testdatabase that you can use to test MySQL. The program also creates privilege table entries for the initial account or accounts.
test_. For a complete listing and description of the grant tables, see Access Control and Account Management.
It might be necessary to specify other options such as
--datadirif mysql_install_db cannot identify the correct locations for the installation directory or data directory. For example (enter the command on a single line):
scripts/mysql_install_db --user=mysql --basedir=/opt/mysql/mysql --datadir=/opt/mysql/mysql/data
For a more secure installation, invoke mysql_install_db with the
--random-passwordsoption. This causes it to assign a random password to the MySQL
rootaccounts, set the “password expired” flag for those accounts, and remove the anonymous-user MySQL accounts. For additional details, see mysql_install_db — Initialize MySQL Data Directory. (Install operations using RPMs for Unbreakable Linux Network are unaffected because they do not use mysql_install_db.)
If you do not want to have the
testdatabase, you can remove it after starting the server, using the instructions in Securing the Initial MySQL Accounts.
If you have trouble with mysql_install_db at this point, see Section 5.1, “Problems Running mysql_install_db”.
In the absence of any option files, the server starts with its default settings. (See Server Configuration Defaults.) To specify options that the MySQL server should use at startup, put them in an option file such as
/etc/mysql/my.cnf. (See Using Option Files.) For example, you can use an option file to set the
To arrange for MySQL to start without manual intervention at system boot time, see Starting and Stopping MySQL Automatically.
Data directory initialization creates time zone tables in the
mysqldatabase but does not populate them. To do so, use the instructions in MySQL Server Time Zone Support.