单选题You backed up the database at 8 a.m. today using an online backup. Accounting made a large change to the underlying data between 10 a.m. and noon.  Which of the following actions would ensure that the changes could be recovered using the 8 a.m. backup？

第1题：

You database operates in ARCHIVELOG mode and user-managed consistent backups are performed every Sunday night. On Tuesday， at 9：00 a.m. the current log sequence number was 369. Also， on Tuesday you lost the data file belonging to the SYSTEM tablespace and an achivelog file （sequence number 356） that contained redo entries between 8：00 a.m. and 8.30 a.m. With reference to this scenario， what would you do to recover the database？（）

• A、 Restore all the data files from last Sunday’s backup， and then perform a time-based recovery.
• B、 Restore all the data files from last Sunday’s backup， and then perform a cancel-based recovery.
• C、 Restore all the data files from last Sunday’s backup， and then perform a change-based recovery.
• D、 Restore only data files that belong to the SYSTEM tablespace from last Sunday’s backup， and then perform a complete recovery.

第2题：

The application workload on your database is same between 10 a.m. and 11 a.m. on weekdays. Suddenly you observe poor performance between 10 a.m. and 11 a.m. in the middle of the week. How would you identify the changes in configuration settings， workload profile， and statistics to diagnose the possible causes of the performance degradation？（）

• A、by using the SQL access advisor
• B、by using the Automatic Workload Repository report
• C、by running the Automatic Database Diagnostic Monitor （ADDM）
• D、by using the Automatic Workload Repository Compare Period report
• E、by analyzing the output of the V$ACTIVE_SESSION_HISTORY view

第3题：

In Recovery Manager （RMAN）， you have set control file autobackup to ON by using the following command：  CONFIGURE CONTROLFILE AUTOBACKUP ON;  Which two events would cause the control file to be backed up automatically？ （）

• A、a tablespace is taken offline
• B、the database instance is restarted
• C、a new data file is added to an existing tablespace
• D、a successful backup is recorded in the RMAN repository
• E、the RMAN connection is disconnected from the target database

第4题：

Your database is in ARCHIVELOG mode. On Friday evening， you perform an online database backup by using the BACKUP DATABASE command at the Recovery Manager （RMAN） prompt and close the  database. On Monday， the System Administrator informs you about the failure of two hard disks. One of the lost disks contains two datafiles， HR1.DBF and HR2.DBF， both of which belong to a read/write tablespace named HR. The disk also contains a datafile， USERS.DBF， which belongs to a read/write tablespace named USERS. You need to restore and recover the database backup that was performed on Friday evening. After mounting the database， you issue the following RMAN commands：        RMAN>RESTORE DATABASE；        RMAN>RECOVER DATABASE；   After successfully executing these RMAN commands， you issue the following statement using SQL*Plus：        SQL>ALTER DATABASE OPEN；   You receive the following errors when attempting to open the database：        ORA-01157： cannot identify/lock data file 10 see DBWR trace file        ORA-01110： data file 10： ’D:///USERS.DBF’   What is the cause of these errors？（）

• A、 The USERS.DBF datafile is corrupted and cannot be restored by RMAN.
• B、 The USERS.DBF datafile was not backed up using the RMAN BACKUP DATABASE command.
• C、 The USERS.DBF datafile was not restored using the RMAN RESTORE DATABASE command.
• D、 The USERS.DBF datafile was not recovered using the RMAN RECOVER DATABASE command.

第5题：

You are maintaining the PROD database for NetFx Corporation. You have configured controlfile autobackup in your database. At 6：00 P.M. on Monday， you issue the following command：       RMAN>BACKUP DATABASE；  At 8：00 A.M. on Tuesday， you are unable to start the database because all the control files are missing. You decide to restore the control files from the backup by using the RMAN> RESTORE CONTROLFILE FROM AUTOBACKUP； command. Which operation should you perform before using the RMAN> RESTORE CONTROLFILE FROM AUTOBACKUP； command？（）

• A、 Start the database in the MOUNT stage.
• B、 Back up the control file to trace.
• C、 Set the DBID
• D、 Issue the RECOVER DATABASE command.

第6题：

Examine the following command used to perform incremental level 0 backup：   RMAN> BACKUP INCREMENTAL LEVEL 0 DATABASE；   To enable the block change tracking， after the incremental level 0 backup you issued the following command：   SQL> ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE ’/mydir/ rman_change_track.f’；To perform incremental level 1 cumulative backup， you issued the following command：   RMAN> BACKUP INCREMENTAL LEVEL 1 CUMULATIVE DATABASE；   Which two statements are true in the above situation？（）

• A、 The block change tracking data will be used only from the next incremental 0 backup.
• B、 The incremental backup will use change tracking data for accomplishing the backup.
• C、 The incremental backup will not use change tracking data for accomplishing the backup.
• D、 The block track file will scan all the blocks and create bitmap for all the blocks backed up in the level 0 backup.

第7题：

The current time is 12：00 noon. You want to recover the USERS tablespace from a failure that occurred at 11：50 a.m. You discover that the only member of an unarchived redo log group containing information from 11：40 a.m. onwards is corrupt. With reference to this scenario， if you are not using Recovery Manager （RMAN）， which recovery method would you use？（）

• A、 time-based recovery
• B、 log sequence recovery
• C、 cancel-based recovery
• D、 change-based recovery

第8题：

Your PROD database has been started using the server parameter file. In your PROD database you are using RMAN for backup and recovery operations. You issue the following commands from the RMAN prompt：     RMAN> CONFIGURE CONTROLFILE AUTOBACKUP OFF；   RMAN> BACKUP DATABASE；   Which files from the database will be backed up as a result of this BACKUP command？（）

• A、 control file
• B、 all datafiles
• C、 password file
• D、 online redo log file
• E、 archive redo log file
• F、 server parameter file
• G、 only the SYSTEM datafile

第9题：

You are using RMAN to backup your ARCHIVELOG mode database. You have enabled control-file autobackups. Which files are not backed up during the RMAN backup?（）

• A、Database Datafiles 
• B、Database Control Files 
• C、Online redo logs
• D、Archived redo logs 
• E、The database SPFILE 
• F、None of the above, all these files are backed up. 

第10题：

The current time is 12：00 noon. You want to recover the USERS tablespace from a failure that occurred at 11：50 a.m. You discover that the only member of an unarchived redo log group containing information from 11：40 a.m. onwards is corrupt.  With reference to this scenario， if you are not using Recovery Manager （RMAN）， which recovery method would you use？（）

• A、time­based recovery
• B、log sequence recovery
• C、cancel­based recovery
• D、change­based recovery