Your database is open and running in ARCHIVELOG mode. You take RMAN full backups every Sunday night. On Monday morning， while querying the user1.employees table， you receive the following error message： 
01578： ORACLE data block corrupted （file # 5， block # 51） ORA-01110： data file 5： 
’/u01/app/oracle/oradata/orcl/example01.dbf’ 
You need to rectify the corruption while ensuring the following： The data file should remain online. 
The mean time to recover （MTTR） should be minimal. 
You are not using a backup control file， and all the archived logs are accessible.  
Which option would you choose？（）

单项选择题TheDB_BLOCK_CHECKINGinitializationparameterissettoTRUE.Whatwouldbetheresultofthissettingonthedatablocksbeingwrittentothedatafiles，everytimetheDBWnwrites？（）

A.The Oracle database will check all data blocks by going through the data on each block， making sure the data is self-consistent.
B.DBWn and the direct loader will calculate a checksum and store it in the cache header of every data block when writing it to disk.
C.The Oracle database will check data blocks belonging to the SYSTEM tablespace only， by going through the data on each block， making sure the data is self-consistent.
D.The Oracle database will check data blocks belonging to the SYSAUX tablespace only， by going through the data on each block， making sure the data is self-consistent.
E.The Oracle database will check data blocks in the SYSTEM and SYSAUX tablespaces only， by going through the data on each block， making sure the data is self-consistent

单项选择题TheEMPLOYEEStableisstoredintheUSERStablespace.YouneedtocheckiftheEMPLOYEEStableisaffectedbytheblockcorruptionfoundintheUSERStablespace.Whichoptionwouldyouuse？（）

A.the DBNEWID utility
B.the ANALYZE command
C.the RMAN LIST command
D.the RMAN REPORT command
E.the RMAN CROSSCHECK command
F.the RMAN BLOCKRECOVER command

单项选择题Therewasmediafailureandyouneedtocheckthedatafilesforanyblockcorruption.Whichoptionwouldyouusetocreateareportonanycorruptionsfoundwithinthedatabase？（）

A.the DBNEWID utility
B.the DBVERIFY utility
C.the ANALYZE command
D.the RMAN REPORT command
E.the RMAN CROSSCHECK command
F.the CHECK_OBJECT procedure of the DBMS_REPAIR package

单项选择题Byusingthetransactionidentifierprovidedby（）foraparticularrowchange，youcanusetheFlashbackTransactionQuerytoseetheoperationperformedbythetransaction.

A.Flashback Table
B.Flashback Database
C.Flashback Versions Query
D.the RMAN REPORT command
E.the DBA_PENDING_TRANSACTIONS view

单项选择题You executed the following query： SELECT operation， undo_sql， table_name FROM flashback_transaction_query；  Which statement is correct regarding the query output？（）

A.It would return information regarding only the last committed transaction.
B.It would return only the active transactions in all the undo segments in the database.
C.It would return only the committed transactions in all the undo segments in the database.
D.It would return both active and committed transactions in all the undo segments in the database.
E.It would return information regarding the transactions that began and were committed in the last 30 minutes.