Server plugins must be loaded in to the server before they can be used. MySQL enables you to load a plugin at server startup or at runtime. It is also possible to control the activation of loaded plugins at startup, and to unload them at runtime.
Server plugins must be known to the server before they can be
used. A plugin can be made known several ways, as described
here. In the following descriptions,
plugin_name stands for a plugin name
A plugin that is built in to the server is known by the server
automatically. Normally, the server enables the plugin at
startup, although this can be changed with the
Plugins registered in the
mysql.plugin table serves as a registry
of plugins. The server normally enables each plugin listed in
the table at startup, although whether a given plugin is enabled
can be changed with the
option. If the server is started with the
--skip-grant-tables option, it
does not consult this table and does not load the plugins listed
Plugins named with the
A plugin that is located in a plugin library file can be loaded
at server startup with the
--plugin-load option. Normally,
the server enables the plugin at startup, although this can be
changed with the
The option value is a semicolon-separated list of
name is the name of the
plugin_library is the
name of the shared library that contains the plugin code. If a
plugin library is named without any preceding plugin name, the
server loads all plugins in the library. Each library file must
be located in the directory named by the
plugin_dir system variable.
This option does not register any plugin in the
mysql.plugin table. For subsequent restarts,
the server loads the plugin again only if
--plugin-load is given again.
That is, this option effects a one-time installation that
persists only for one server invocation.
--plugin-load enables plugins to
be loaded even when
--skip-grant-tables is given
(which causes the server to ignore the
--plugin-load also enables
plugins to be loaded at startup under configurations when
plugins cannot be loaded at runtime.
Plugins installed with the
A plugin that is located in a plugin library file can be loaded
at runtime with the
PLUGIN statement. The statement also registers the
plugin in the
mysql.plugin table to cause the
server to load it on subsequent restarts. For this reason,
INSTALL PLUGIN requires the
INSERT privilege for the
If a plugin is named both using a
--plugin-load option and in the
mysql.plugin table, the server starts but
writes these messages to the error log:
100310 19:15:44 [ERROR] Function '
plugin_name' already exists 100310 19:15:44 [Warning] Couldn't load plugin named '
plugin_name' with soname '
installs a plugin at server startup. To install a plugin named
myplugin in a plugin library file named
somepluglib.so, use these lines in a
In this case, the plugin is not registered in
mysql.plugin. Restarting the server without
--plugin-load option causes
the plugin not to be loaded at startup.
statement causes the server to load the plugin code from the
library file at runtime:
INSTALL PLUGIN myplugin SONAME 'somepluglib.so';
INSTALL PLUGIN also causes
“permanent” plugin registration: The server lists
the plugin in the
mysql.plugin table to
ensure that it is loaded on subsequent server restarts.
Many plugins can be loaded either at server startup or at
runtime. However, if a plugin is designed such that it must be
loaded and initialized during server startup, use
--plugin-load rather than
While a plugin is loaded, information about it is available at
runtime from several sources, such as the
SHOW PLUGINS statement.
For more information, see
Section 126.96.36.199, “Obtaining Server Plugin Information”.
If the server knows about a plugin when it starts (for example,
because the plugin is named using a
--plugin-load option or
registered in the
mysql.plugin table), the
server loads and enables the plugin by default. It is possible
to control activation for such a plugin using a
startup option named after the plugin. In the following
plugin_name stands for
a plugin name such as
csv. As with other options, dashes and
underscores are interchangeable in option names. For example,
--my-plugin=ON are equivalent.
As of MySQL 5.1.36, these options control plugin loading:
Tells the server to disable the plugin.
Tells the server to enable the plugin. (Specifying the
without a value has the same effect.) If the plugin fails to
initialize, the server runs with the plugin disabled.
Tells the server to enable the plugin, but if plugin initialization fails, the server does not start. In other words, this option forces the server to run with the plugin enabled or not at all.
FORCE are not case sensitive.
built-in pluggable storage engines and that you want the server
to load them at startup, subject to these conditions: The server
is permitted to run if
fails, but must require that
initialization succeeds, and
be disabled. To accomplish that, use these lines in an option
[mysqld] csv=ON blackhole=FORCE archive=OFF
option format is supported as a synonym for
option formats are supported as synonyms for
Before MySQL 5.1.36, plugin options are boolean options (see Section 4.2.5, “Program Option Modifiers”). That is, any of these options enable the plugin:
And these options disable the plugin:
If you upgrade to MySQL 5.1.36 or later from an older version
and previously used options of the form
equivalent options are now
respectively. You also have the choice of requiring plugins to
start successfully by using
If a plugin is disabled, either explicitly with
OFF or implicitly because it was enabled with
ON but failed to initialize, aspects of
server operation that require the plugin will change. For
example, if the plugin implements a storage engine, existing
tables for the storage engine become inaccessible, and attempts
to create new tables for the storage engine result in tables
that use the default storage engine unless the
mode has been enabled to cause an error to occur instead.
Disabling a plugin may require adjustment to other options. For
example, if you start the server using
options likely will need to be omitted from the startup command.
In addition, if the server is configured to use
InnoDB as the default storage
engine, it will not start unless you specify another available
storage engine with
A plugin known to the server can be uninstalled to disable it at
runtime with the
statement. The statement unloads the plugin and removes it from
mysql.plugin table if it is registered
there. For this reason,
PLUGIN statement requires the
DELETE privilege for the
mysql.plugin table. With the plugin no longer
registered in the table, the server will not load the plugin
automatically for subsequent restarts.
UNINSTALL PLUGIN cannot unload
plugins that are built in to the server. These can be identified
as those that have a library name of
the output from