DBA_HIST_BG_EVENT_SUMMARY

DBA_HIST_BG_EVENT_SUMMARY displays the historical summary background event activity. This view contains snapshots from V$SESSION_EVENT.

Column	Datatype	NULL	Description
`SNAP_ID`	`NUMBER`	`NOT NULL`	Unique snapshot ID
`DBID`	`NUMBER`	`NOT NULL`	Database ID for the snapshot
`INSTANCE_NUMBER`	`NUMBER`	`NOT NULL`	Instance number for the snapshot
`EVENT_ID`	`NUMBER`	`NOT NULL`	Identifier of the wait event
`EVENT_NAME`	`VARCHAR2(64)`	`NOT NULL`	Name of the wait event
`WAIT_CLASS_ID`	`NUMBER`		Identifier of the class of the wait event
`WAIT_CLASS`	`VARCHAR2(64)`		Name of the class of the wait event
`TOTAL_WAITS`	`NUMBER`		Total number of waits for the event
`TOTAL_TIMEOUTS`	`NUMBER`		Total number of timeouts for the event
`TIME_WAITED_MICRO`	`NUMBER`		Total amount of time waited for the event (in microseconds)