052-47

　　Your database instance is functional for the past one month. The Automatic Workload Repository(AWR) snapshot retention is set to 7 and the STATISTICS_LEVEL initialization parameter is set to TYPICAL.
　　You receive a complaint about the poor performance of the database between 7 PM and 9 PM of the previous day.
　　Choose two actions any of which can be referred to first to diagnose the problem. (Choose two.)
A.Use the Active Session History report.
B.Use the AWR Compare Periods report.
C.Use an ADDM analysis between 7 PM and 9 PM of the previous day.
D.Use the AWR Compare Period report between 7 PM and 9 PM of the previous day

A 不正确，因为一般 Active Session History 默认保留时间为 1 小时，所以无法查前天的信息
D 不正确，因为应该与正常时段对比来确认问题