The Error Log Consider a server started with this setting: In this case,  log_error_verbosity  permits messages with  ERROR  priority and discards messages with WARNING  or  INFORMATION  priority. Setting  log_error_suppression_list  has no effect because all error codes it might suppress are already discarded due to the  log_error_verbosity  setting. The  log_filter_dragnet  log filter component enables log filtering based on user-defined rules. To enable the  log_filter_dragnet  filter, first load the filter component, then modify the log_error_services  value. The following example enables  log_filter_dragnet  in combination with the built-in log sink: To set  log_error_services  to take effect at server startup, use the instructions at Section 5.4.2.1, “Error Log Configuration” . Those instructions apply to other error-logging system variables as well. With  log_filter_dragnet  enabled, define its filter rules by setting the dragnet.log_error_filter_rules  system variable. A rule set consists of zero or more rules, where each rule is an  IF  statement terminated by a period ( . ) character. If the variable value is empty (zero rules), no filtering occurs. Example 1. This rule set drops information events, and, for other events, removes the  source_line  field: The effect is similar to the filtering performed by the  log_sink_internal  filter with a setting of log_error_verbosity=2 . For readability, you might find it preferable to list the rules on separate lines. For example: Example 2: This rule limits information events to no more than one per 60 seconds: Once you have the filtering configuration set up as you desire, consider assigning dragnet.log_error_filter_rules  using  SET PERSIST  rather than  SET GLOBAL  to make the setting persist across server restarts. Alternatively, add the setting to the server option file. To stop using the filtering language, first remove it from the set of error logging components. Usually this means using a different filter component rather than no filter component. For example: Again, consider using using  SET PERSIST  rather than  SET GLOBAL  to make the setting persist across server restarts. 1035 SET GLOBAL log_error_services = ’log_filter_internal; log_sink_internal’; SET GLOBAL dragnet.log_error_filter_rules = ’IF prio>=INFORMATION THEN throttle 1/60.’; SET GLOBAL dragnet.log_error_filter_rules = ’ IF prio>=INFORMATION THEN drop. IF EXISTS source_line THEN unset source_line. ’; SET GLOBAL dragnet.log_error_filter_rules = ’IF prio>=INFORMATION THEN drop. IF EXISTS source_line THEN unset source_line.’; INSTALL COMPONENT ’file://component_log_filter_dragnet’; SET GLOBAL log_error_services = ’log_filter_dragnet; log_sink_internal’; [mysqld] log_error_verbosity=1 # error messages only 5.4.2.6 Rule-Based Error Log Filtering (log_filter_dragnet)