多项选择题
A.A role can be granted to itself.
B.Roles are owned by the SYS user.
C.Roles can be granted to other roles.
D.A role cannot be assigned external authentication.
E.A role can contain both system and object privileges.
单项选择题 Youareworkingonanonlinetransactionprocessing（OLTP）system.YounoticethataPL/SQLproceduregotexecutedtwiceat2）00p.m.ThishasincorrectlyupdatedtheEMP_SALtable.Howwouldyourevertthetabletoitsstateat2）00p.m.？（）
单项选择题 YourtestdatabaseisrunninginNOARCHIVELOGmode.Whataretheimplicationsofthis？（）
单项选择题 TheSAVE_AMTcolumnintheACCOUNTStablecontainsthebalancedetailsofcustomersinabank.Aspartoftheyear-endtaxandinterestcalculationprocess，alltherowsinthetableneedtobeaccessed.Thebankauthoritieswanttotrackaccesstotherowscontainingbalanceamountsexceeding$200，000，andthensendanalertmessagetotheadministrator.Whichmethodwouldyousuggesttothebankforachievingthistask？（）