Query Cache Information Plugin

The QUERY_CACHE_INFO plugin creates the QUERY_CACHE_INFO table in the INFORMATION_SCHEMA database. This table shows all queries in the query cache. Querying this table acquires the query cache lock and will result in lock waits for queries that are using or expiring from the query cache. You must have the PROCESS privilege to query this table.

Installing the Plugin

Although the plugin's shared library is distributed with MariaDB by default, the plugin is not actually installed by MariaDB by default. There are two methods that can be used to install the plugin with MariaDB.

The first method can be used to install the plugin without restarting the server. You can install the plugin dynamically by executing or :

The second method can be used to tell the server to load the plugin when it starts up. The plugin can be installed this way by providing the or the options. This can be specified as a command-line argument to or it can be specified in a relevant server in an :

Uninstalling the Plugin

You can uninstall the plugin dynamically by executing or :

If you installed the plugin by providing the or the options in a relevant server in an , then those options should be removed to prevent the plugin from being loaded the next time the server is restarted.

Example

Options

query_cache_info

• Description: Controls how the server should treat the plugin when the server starts up.

  • Valid values are:

    • OFF - Disables the plugin without removing it from the table.

_{This page is licensed: CC BY-SA / Gnu FDL}