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

本站中文解释

Oracle视图DBA_OPTSTAT_OPERATION_TASKS显示数据库内最近被实行的优化绩效管理任务的信息。该视图可以用来显示运行在时间跨度内运行的不同事件，如自动收集绩效统计信息、分析器优化等。该视图可以用来监控优化器操作状态，并根据需要记录或删除这些数据，以及监视优化绩效管理任务的执行情况。

官方英文解释

DBA_OPTSTAT_OPERATION_TASKS displays the history of tasks that are performed as part of statistics operations (recorded in DBA_OPTSTAT_OPERATIONS). Each task represents a target object to be processed in the corresponding parent operation.

Column	Datatype	Description
`OPID`	`NUMBER`	Internal identifier for the statistics operation that the task belongs to
`TARGET`	`VARCHAR2(100)`	Name of the object that this task operates on
`TARGET_OBJN`	`NUMBER`	Object number of the target object
`TARGET_TYPE`	`VARCHAR2(40)`	Type of the target object. Possible values are: `TABLE` `TABLE (GLOBAL STATS ONLY)`: Task is created to gather only global statistics of a partitioned table `TABLE (COORDINATOR JOB)`: Coordinator task for a partitioned table when concurrency is on `TABLE PARTITION` `TABLE SUBPARTITION` `INDEX` `INDEX PARTITION` `INDEX SUBPARTITION`
`TARGET_SIZE`	`NUMBER`	Target size (in number of blocks) when the task started
`START_TIME`	`TIMESTAMP(6) WITH TIME ZONE`	Task start time
`END_TIME`	`TIMESTAMP(6) WITH TIME ZONE`	Task end time
`STATUS`	`VARCHAR2(49)`	Current task status. Possible values are: `PENDING`: Task is queued for processing `IN PROGRESS`: Task is currently running `COMPLETED`: Task has completed successfully `FAILED`: Task has failed `SKIPPED`: Task has been skipped, as it does not exist any more, or its stats are not stale (applies only to only automatic statistics gathering) `TIMED OUT`: Maintenance window was not enough to complete this task (applies only to automatic statistics gathering)
`JOB_NAME`	`VARCHAR2(50)`	Name of the scheduler job that executes this task (for example, when concurrency is on)
`ESTIMATED_COST`	`NUMBER`	Estimated cost of the task (measured as elapsed time in seconds). This column is populated only when concurrency is on.
`BATCHING_COEFF`	`NUMBER`	For internal use only
`ACTIONS`	`NUMBER`	For internal use only
`PRIORITY`	`NUMBER`	Rank of the task among all target objects for the parent operation
`FLAGS`	`NUMBER`	For internal use only
`NOTES`	`VARCHAR2(4000)`	Notes about the underlying task, such as the failure message for tasks with status `FAILED`.