Oracle 视图 DBA_HIST_BG_EVENT_SUMMARY 官方解释，作用，如何使用详细说明

本站中文解释

(ORACLE11G以上 )

Oracle视图DBA_HIST_BG_EVENT_SUMMARY用于查看背景进程运行事件的历史汇总数据，包括活动事件名称、活动事件ID、开始时间、结束时间、状态和同事件ID次数等等，可以用来分析系统在每一时刻背景进程的活动。

这个视图的使用方法就和使用其它的视图一样，通过select语句即可查看它的内容，如： select * from DBA_HIST_BG_EVENT_SUMMARY；当然，你也可以根据自己的需求，使用这个视图提供的关键字如event_name,event_id,start_time,end_time,status,occurences等，并用其与其他视图关联，查看需要的相关信息。

官方英文解释

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)
`CON_DBID`	`NUMBER`		The database ID of the PDB for the sampled session
`CON_ID`	`NUMBER`		The ID of the container that `CON_DBID` identifies. Possible values include: `0`: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs. `1`: This value is used for rows containing data that pertain to only the root n: Where n is the applicable container ID for the rows containing data