mysqld - the MySQL server
, also known as MySQL Server, is the main program that does most of
the work in a MySQL installation. MySQL Server manages access to the MySQL
data directory that contains databases and tables. The data directory is also
the default location for other information such as log files and status files.
Some installation packages contain a debugging version of the server named
. Invoke this version instead of mysqld
debugging support, memory allocation checking, and trace file support (see
Section 188.8.131.52, “Creating Trace Files”).
When MySQL server starts, it listens for network connections from client
programs and manages access to databases on behalf of those clients.
program has many options that can be specified at startup. For
a complete list of options, run this command:
shell> mysqld --verbose --help
MySQL Server also has a set of system variables that affect its operation as it
runs. System variables can be set at server startup, and many of them can be
changed at runtime to effect dynamic server reconfiguration. MySQL Server also
has a set of status variables that provide information about its operation.
You can monitor these status variables to access runtime performance
For a full description of MySQL Server command options, system variables, and
status variables, see Section 5.1, “The MySQL Server”.
For information about installing MySQL and setting up the initial
configuration, see Chapter 2, Installing and Upgrading MySQL.
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only under the terms of the GNU General Public License as published by the
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For more information, please refer to the MySQL Reference Manual, which may
already be installed locally and which is also available online at
Oracle Corporation (http://dev.mysql.com/).