单项选择题
A.V$DATAFILE
B.V$TEMPFILE
C.V$DBFILE
D.V$DATAFILE_HEADER
单项选择题 RMANenablesyoutoopenthetargetdatabasewhenitisalreadymounted.WhichcommandmustyouexecuteattheRMANprompttoopenthedatabase？（）
单项选择题 Whichofthefollowingcommandscannotbeexecutedwhenthedatabaseopen？（）
单项选择题 Whichofthefollowingviewsmustyouquerytoidentifyanycorruptdatafileblocksthathavebeendetectedduringbackupsetcreation？（）