Obtaining Component Information A component when installed may also automatically install related loadable functions. If so, the component when uninstalled also automatically uninstalls those functions. The  mysql.component  sytem table contains information about currently loaded components and shows which components have been registered using  INSTALL COMPONENT . Selecting from the table shows which components are installed. For example: The  component_id  and  component_group_id  values are for internal use. The  component_urn  is the URN used in  INSTALL COMPONENT  and  UNINSTALL COMPONENT  statements to load and unload the component. This section describes the characteristics of individual error log components. For general information about configuring error logging, see Section 5.4.2, “The Error Log” . A log component can be a filter or a sink: •A filter processes log events, to add, remove, or modify event fields, or to delete events entirely. The resulting events pass to the next log component in the list of enabled components. •A sink is a destination (writer) for log events. Typically, a sink processes log events into log messages that have a particular format and writes these messages to its associated output, such as a file or the system log. A sink may also write to the Performance Schema  error_log  table; see Section 27.12.21.1, “The error_log Table” . Events pass unmodified to the next log component in the list of enabled components (that is, although a sink formats events to produce output messages, it does not modify events as they pass internally to the next component). •Filter Error Log Components •Sink Error Log Components •The component name and intended purpose. •Whether the component is built in or must be loaded. For a loadable component, the description specifies the URN to use to load and unload the component with the  INSTALL COMPONENT  and UNINSTALL COMPONENT  statements. •Whether the component can be listed multiple times in the  log_error_services  value. •For a sink component, the destination to which the component writes output. 5.5.2 Obtaining Component Information 5.5.3 Error Log Components mysql>  SELECT * FROM mysql.component; +--------------+--------------------+------------------------------------+ | component_id | component_group_id | component_urn | +--------------+--------------------+------------------------------------+ | 1 | 1 | file://component_validate_password | | 2 | 2 | file://component_log_sink_json | +--------------+--------------------+------------------------------------+ The  log_error_services  system variable value lists the enabled log components. Components not named in the list are disabled. The following sections describe individual log components, grouped by component type: Component descriptions include these types of information: 1070