MySQL 5.6 Reference Manual Including MySQL NDB Cluster 7.3-7.4 Reference Guide
INSTALL PLUGINplugin_name
SONAME 'shared_library_name
'
This statement installs a server plugin. It requires the
INSERT
privilege for the
mysql.plugin
system table because it adds a
row to that table to register the plugin.
plugin_name
is the name of the plugin
as defined in the plugin descriptor structure contained in the
library file (see Plugin Data Structures).
Plugin names are not case-sensitive. For maximal compatibility,
plugin names should be limited to ASCII letters, digits, and
underscore because they are used in C source files, shell
command lines, M4 and Bourne shell scripts, and SQL
environments.
shared_library_name
is the name of
the shared library that contains the plugin code. The name
includes the file name extension (for example,
libmyplugin.so
,
libmyplugin.dll
, or
libmyplugin.dylib
).
The shared library must be located in the plugin directory (the
directory named by the
plugin_dir
system variable).
The library must be in the plugin directory itself, not in a
subdirectory. By default,
plugin_dir
is the
plugin
directory under the directory named
by the pkglibdir
configuration variable, but
it can be changed by setting the value of
plugin_dir
at server startup.
For example, set its value in a my.cnf
file:
[mysqld]
plugin_dir=/path/to/plugin/directory
If the value of plugin_dir
is a
relative path name, it is taken to be relative to the MySQL base
directory (the value of the
basedir
system variable).
INSTALL PLUGIN
loads and
initializes the plugin code to make the plugin available for
use. A plugin is initialized by executing its initialization
function, which handles any setup that the plugin must perform
before it can be used. When the server shuts down, it executes
the deinitialization function for each plugin that is loaded so
that the plugin has a chance to perform any final cleanup.
INSTALL PLUGIN
also registers the
plugin by adding a line that indicates the plugin name and
library file name to the mysql.plugin
system
table. During the normal startup sequence, the server loads and
initializes plugins registered in
mysql.plugin
. This means that a plugin is
installed with INSTALL PLUGIN
only once, not every time the server starts. If the server is
started with the
--skip-grant-tables
option,
plugins registered in the mysql.plugin
table
are not loaded and are unavailable.
A plugin library can contain multiple plugins. For each of them
to be installed, use a separate INSTALL
PLUGIN
statement. Each statement names a different
plugin, but all of them specify the same library name.
INSTALL PLUGIN
causes the server
to read option (my.cnf
) files just as
during server startup. This enables the plugin to pick up any
relevant options from those files. It is possible to add plugin
options to an option file even before loading a plugin (if the
loose
prefix is used). It is also possible to
uninstall a plugin, edit my.cnf
, and
install the plugin again. Restarting the plugin this way enables
it to the new option values without a server restart.
For options that control individual plugin loading at server
startup, see Section 5.5.1, “Installing and Uninstalling Plugins”. If you need to
load plugins for a single server startup when the
--skip-grant-tables
option is
given (which tells the server not to read system tables), use
the --plugin-load
option. See
Section 5.1.6, “Server Command Options”.
To remove a plugin, use the UNINSTALL
PLUGIN
statement.
For additional information about plugin loading, see Section 5.5.1, “Installing and Uninstalling Plugins”.
To see what plugins are installed, use the
SHOW PLUGINS
statement or query
the INFORMATION_SCHEMA
the
PLUGINS
table.
If you recompile a plugin library and need to reinstall it, you can use either of the following methods:
Use UNINSTALL PLUGIN
to
uninstall all plugins in the library, install the new plugin
library file in the plugin directory, and then use
INSTALL PLUGIN
to install all
plugins in the library. This procedure has the advantage
that it can be used without stopping the server. However, if
the plugin library contains many plugins, you must issue
many INSTALL PLUGIN
and
UNINSTALL PLUGIN
statements.
Stop the server, install the new plugin library file in the plugin directory, and restart the server.