多项选择题
A.the retention period to support flashback
B.the expected length of the longest-running query
C.the number of undo tablespaces in the database
D.the size of the Flash Recovery Area for the database instance
单项选择题 WhichstatementistrueabouttheUNDO_RETENTIONparameterwhenretentionguaranteeisnotenabled()
单项选择题 InwhichsituationmaytheUNDO_RETENTIONparameterbeignored,evenifitissettoavalue()
单项选择题 YourdatabaseinstanceisconfiguredwithautomaticundomanagementandtheUNDO_RETENTIONparameterissetto900seconds.Youexecutedthefollowingcommandtoenableretentionguarantee:SQL>ALTERTABLESPACEundotbs1RETENTIONGUARANTEE;Whateffectwouldthiscommandhaveonthedatabase()