YourdatabaseisinARCHIVELOGmode.OnFridayevening,youperformanonlinedatabasebackupbyusingtheBACKUPDATABASEcommandattheRecoveryManager(RMAN)promptandclosethedatabase.OnMonday,theSystemAdministratorinformsyouaboutthefailureoftwoharddisks.Oneofthelostdiskscontainstwodatafiles,HR1.DBFandHR2.DBF,bothofwhichbelongtoaread/writetablespacenamedHR.Thediskalsocontainsadatafile,USERS.DBF,whichbelongstoaread/writetablespacenamedUSERS.YouneedtorestoreandrecoverthedatabasebackupthatwasperformedonFridayevening.Aftermountingthedatabase,youissuethefollowingRMANcommands:RMANRESTOREDATABASE;RMANRECOVERDATABASE;AftersuccessfullyexecutingtheseRMANcommands,youissuethefollowingstatementusingSQL*Plus:SQLALTERDATABASEOPEN;Youreceivethefollowingerrorswhenattemptingtoopenthedatabase:ORA-01157:cannotidentify/lockdatafile10seeDBWRtracefileORA-01110:datafile10:’D:\USERS.DBF’Whatisthecauseoftheseerrors?()
YourdatabaseisinARCHIVELOGmode.OnFridayevening,youperformanonlinedatabasebackupbyusingtheBACKUPDATABASEcommandattheRecoveryManager(RMAN)promptandclosethe
database.OnMonday,theSystemAdministratorinformsyouaboutthefailureoftwoharddisks.Oneofthelostdiskscontainstwodatafiles,HR1.DBFandHR2.DBF,bothofwhichbelongtoaread/writetablespacenamedHR.Thediskalsocontainsadatafile,USERS.DBF,whichbelongstoaread/writetablespacenamedUSERS.YouneedtorestoreandrecoverthedatabasebackupthatwasperformedonFridayevening.Aftermountingthedatabase,youissuethefollowingRMANcommands:
RMAN>RESTOREDATABASE;
RMAN>RECOVERDATABASE;
AftersuccessfullyexecutingtheseRMANcommands,youissuethefollowingstatementusingSQL*Plus:
SQL>ALTERDATABASEOPEN;
Youreceivethefollowingerrorswhenattemptingtoopenthedatabase:
ORA-01157:cannotidentify/lockdatafile10seeDBWRtracefile
ORA-01110:datafile10:’D:\USERS.DBF’
Whatisthecauseoftheseerrors?()