Performance Schema Miscellaneous Tables Account status is collected when sessions terminate. The session status counters are added to the global status counters and the corresponding account status counters. If account statistics are not collected, the session status is added to host and user status, if host and user status are collected. The Performance Schema supports  TRUNCATE TABLE  for status variable summary tables as follows; in all cases, status for active sessions is unaffected: Account, host, and user statistics are not collected if the  performance_schema_accounts_size , performance_schema_hosts_size , and  performance_schema_users_size  system variables, respectively, are set to 0. FLUSH STATUS  adds the session status from all active sessions to the global status variables, resets the status of all active sessions, and resets account, host, and user status values aggregated from disconnected sessions. The following sections describe tables that do not fall into the table categories discussed in the preceding sections: Of the logs the MySQL server maintains, one is the error log to which it writes diagnostic messages (see Section 5.4.2, “The Error Log” ). Typically, the server writes diagnostics to a file on the server host or to a system log service. As of MySQL 8.0.22, depending on error log configuration, the server can also write the most recent error events to the Performance Schema  error_log  table. Granting the  SELECT privilege for the  error_log  table thus gives clients and applications access to error log contents using SQL queries, enabling DBAs to provide access to the log without the need to permit direct file system access on the server host. The  error_log  table supports focused queries based on its more structured columns. It also includes the full text of error messages to support more free-form analysis. The table implementation uses a fixed-size, in-memory ring buffer, with old events automatically discarded as necessary to make room for new ones. 5077 27.12.21.1 The error_log Table • user_defined_functions : Loadable functions registered by a component, plugin, or  CREATE FUNCTION  statement. • tls_channel_status : TLS context properties for connection interfaces. • threads : Information about server threads. • performance_timers : Which event timers are available. • log_status : Information about server logs for backup purposes. • host_cache : Information from the internal host cache. • error_log : The most recent events written to the error log. • status_by_user : Resets aggregated user status from terminated sessions. • status_by_host : Resets aggregated host status from terminated sessions. • status_by_account : Aggregates account status from terminated sessions to user and host status, then resets account status. 27.12.21 Performance Schema Miscellaneous Tables