单项选择题
A.An Automatic Workload Repository snapshot has been taken recently.
B.The non-threshold-based alerts are transferred to DBA_ALERT_HISTORY.
C.The threshold alerts conditions are cleared and the alerts are transferred to DBA_ALERT_HISTORY.
D.The threshold alerts related to database metrics are permanently stored in DBA_ALERT_HISTORY but not the threshold alerts related to instance metrics.
单项选择题 The job to gather optimizer statistics for objects runs as part of the automatic maintenance window inyour database instance. At a certain point of time， the maintenance window closes before the statisticsare gathered for all objects. Which statement is true in this scenario（）
多项选择题 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 theprevious day. Choose two actions any of which can be referred to first to diagnose the problem. （）
多项选择题 WhichtwostatementsaretrueabouttheAutomaticDatabaseDiagnosticMonitor（ADDM）（）