Data generated by threshold violation event monitors
Threshold violation event monitors produce data about threshold violations. You can choose to have the output from a database event monitor to regular tables, files or pipes.
Regardless of the output format you choose, all threshold violation event data comes from the event_thresholdviolations logical data group. In addition, if you choose to have the event data written to tables, data from an additional group (CONTROL) is used to generate metadata about the event monitor itself.