多项选择题
A. BEGIN_TIME is the time at which Flashback logging is enabled.
B. END_TIME is the time at which the query is executed on the view.
C. REDO_DATA is the number of bytes of redo data written during the interval.
D. This view contains information about flashback data pertaining to the last 24 hours.
E. FLASHBACK_DATA is the amount of flashback data generated since the database was opened.
单项选择题 YouwererecentlyhiredbyCertkiller.comasadatabaseadministrator.Youareaskedtofindoutwhetherthecurrentlyfunctionallistenerprocess，namedL1，hasbeenpasswordprotectedornot.Youarenotfamiliarwiththefilesystemoftheneworganization.Howwouldyouaccomplishthetask？（）
多项选择题 WhenperformingabackupusingRecoveryManager（RMAN），whichfourtypesoffilescanbebackedupwiththeRMANBACKUPcommand？（）
单项选择题 YouworkasadatabaseadministratoratCertkiller.com.Youareworkinginanonlinetransactionprocessing（OLTP）environment.Yourealizethatthesalaryforanemployee，John，hasbeenaccidentallymodifiedintheEMPLOYEEStable.Twodaysago，thedatawasinthecorrectstate.Flashbacklogsgeneratedduringlasttwodaysareavailableintheflashrecoveryarea.Whichoptionwouldyouchoosetobringthedatatothecorrectstatewhileensuringthatnootherdatainthesametableisaffected？（）