----手工创建oracle 快照
BEGIN
DBMS_WORKLOAD_REPOSITORY.CREATE_SNAPSHOT ();
END;
/

---删除快照
具体快照信息可以查看视图 DBA_HIST_SNAPSHOT

BEGIN
DBMS_WORKLOAD_REPOSITORY.DROP_SNAPSHOT_RANGE (low_snap_id => 22,
high_snap_id => 32, dbid => 3310949047);
END;
/

---修改快照设置
BEGIN
DBMS_WORKLOAD_REPOSITORY.MODIFY_SNAPSHOT_SETTINGS( retention => 43200, interval => 30, topnsql => 100, dbid => 3310949047);
END;
/

/* retention ：43200 minutes (30 days) ；interval：30 minutes ；topsql：    */
通过视图  DBA_HIST_WR_CONTROL 查看当前快照参数配置。