our database is in the MOUNT state and you execute the following command to open it： 
ALTER DATABASE OPEN 
What two actions are performed as a result of this command？（）

单项选择题Anyonewhoknowsjustthehostnameandthelistenernamecanhavefullcontroloverthelistener.Theycanstopthelistenerandalsoobtaindetailedinformationaboutthelistener，database，andtheconfigurationoftheapplication.Howwouldyouavoidthisscenario？（）

A.lock the listener
B.hide the listener
C.create multiple listeners
D.run listener on a remote client
E.set a password for the listener
F.store listener.ora in a non-default location

单项选择题Youareworkingona24x7（available24hoursperday，7daysperweek）productiondatabase.Anoperatingsystem（OS）userdeletesthealertlogfileaccidentally.Whichstatementinthisscenarioistrue？（）

A.The database crashes.
B.The DBA needs to re-create the file.
C.The file gets re-created automatically.
D.The file gets restored automatically from the last backup.
E.The DBA needs to perform a complete database recovery.
F.The DBA needs to perform an incomplete database recovery.

单项选择题Becauseofapoweroutage，instancefailurehasoccurred.Fromwhatpointintheredologdoesrecoverybeginandwheredoesitend？（）

A.current redo log and inactive redo log
B.checkpoint position to end of redo log
C.beginning of redo log to end of redo log
D.all redo logs before the point of last commit
E.beginning of redo log to checkpoint position

单项选择题Itisaholidayandnotransactionsarebeingperformedonthedatabase.YoutookaconsistentbackupofyourdatabasewithoutusingRecoveryManager（RMAN）.HowwouldyoumakeuseofthisconsistentbackupinRMAN？（）

A.cannot be used in RMAN
B.by starting up the database again
C.by using the CATALOG command of RMAN
D.by using the RECOVER CATALOG command in RMAN
E.by re-creating the target control file to rebuild the RMAN repository

单项选择题Oneoftheredologmembersinyourdatabaseislost.YouqueriedV$logfileforfurtherdetails.Whatwouldbethemember’sstatus？（）

A.LOST
B.INVALID
C.EXPIRED
D.DELETED
E.CORRUPT
F.UNKNOWN
G.OBSOLETE