Object Information System Tables Object Information System Tables These system tables contain information about components, loadable functions, and server-side plugins: • component : The registry for server components installed using  INSTALL COMPONENT . Any components listed in this table are installed by a loader service during the server startup sequence. See Section 5.5.1, “Installing and Uninstalling Components” . • func : The registry for loadable functions installed using  CREATE FUNCTION . During the normal startup sequence, the server loads functions registered in this table. If the server is started with the  --skip- grant-tables  option, functions registered in the table are not loaded and are unavailable. See Section 5.7.1, “Installing and Uninstalling Loadable Functions” . • plugin : The registry for server-side plugins installed using  INSTALL PLUGIN . During the normal startup sequence, the server loads plugins registered in this table. If the server is started with the  -- skip-grant-tables  option, plugins registered in the table are not loaded and are unavailable. See Section 5.6.1, “Installing and Uninstalling Plugins” . Like the  mysql.func  system table, the Performance Schema user_defined_functions  table lists loadable functions installed using  CREATE FUNCTION . Unlike the  mysql.func  table, the user_defined_functions  table also lists functions installed automatically by server components or plugins. This difference makes user_defined_functions  preferable to  mysql.func  for checking which functions are installed. See Section 27.12.21.8, “The user_defined_functions Table” . Note These system tables contain server-side help information: The server uses these system tables for logging: For more information, see Section 5.1.17, “Server-Side Help Support” . These system tables contain time zone information: 1020 •  help_topic : Help topic contents. •  help_relation : Mappings between help keywords and topics. •  help_keyword : Keywords associated with help topics. •  help_category : Information about help categories. Time Zone System Tables Server-Side Help System Tables Log System Tables Log tables use the  CSV  storage engine. For more information, see Section 5.4, “MySQL Server Logs” . •  general_log : The general query log table. •  slow_log : The slow query log table.