单选题You work as a database administrator for Supportcenter.cn. Your database is in NOARCHIVELOG mode. The database has been configured with three redo logs groups， and there have been five log switches. You lost one non-system-critical data file from your 

第1题：

The database is running in the ARCHIVELOG mode. It has three redo log groups with one member each. One of the redo log groups has become corrupted. You have issued the following command during the recovery of a damaged redo log file：   ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 3；   Which action should you perform immediately after using this command？（）  

• A、 You should perform a log switch
• B、 You should make a backup of the database
• C、 You should switch the database to the NONARCHIVELOG mode
• D、 You should shut down the database instance and perform a complete database recovery

第2题：

You have recovered your Oracle Database 10g by using the control file backup because all copies of the current control file have been lost due to a media failure. You open your database by using the following statement：       SQL>ALTER DATABASE OPEN RESETLOGS；   Which of the following options is true about using the RESETLOGS option？（）

• A、 The log sequence is reset to 0.
• B、 All the online redo logs are deleted.
• C、 All the archived redo logs from a previous incarnation become useless.
• D、 The full database backup taken from a previous incarnation can be used in future.
• E、 Only the control file and online redo log files are updated with a new RESETLOGS SCN and time stamp.

第3题：

第4题：

You work as a database administrator for Supportcenter.cn. You received the following error while working on your database： ORA-01555： snapshot too old ，In which situation would you receive such an error？（）

• A、You performed rollback after commit.
• B、If a log switch occurs in your database.
• C、Thearchiverfails to generate an archived log file.
• D、Instance recovery fails to find one of the redo log files.
• E、A long-running query is unable to get read-consistent image.
• F、If you perform manual undo management operations in auto mode.

第5题：

Your test database is configured to run in NOARCHIVELOG mode. One of the data files in the USERStablespace is lost due to a media failure. You notice that all the online redo logs have been overwritten since the last backup.  What would you do to recover the data file（）

• A、Take the USERS tablespace offline and re-create the lost data file.
• B、Shut down the instance， restore the data file from the last consistent backup， and restart the databaseinstance.
• C、Shut down the instance， restore all the database files from the last consistent backup， and restart thedatabase instance.
• D、Take the USERS tablespace offline， restore all the data files of the USERS tablespace from the lastconsistent backup， and make the tablespace online.

第6题：

Your database is configured in NOARCHIVELOG mode. All the control files have been lost due to a hard disk failure but the data files are not lost. You have the closed whole database backup available to you.  Which two statements are true in this scenario？（）

• A、The instance aborts.
• B、The database cannot be recovered.
• C、The database can be recovered by restoring the control files from the backup.
• D、The database remains opened and you have to shut it down with the ABORT option.
• E、The database can be restored till the point of the last closed whole database backup.

第7题：

If you create your database using Oracle Managed Files （OMF）， what is true？（）

• A、You must use Oracle predefined names to identify raw partitions that will hold OMF structures. 
• B、You must define directories for two online redo log groups and three copies of the control file. 
• C、If your CREATE DATABASE command fails, any OMF database files that have already been created will be dropped automatically. 
• D、You must use only OMF data files when adding new tablespaces or data files to your database in the future.

第8题：

Your test database is configured to run in NOARCHIVELOG mode. One of the data files in the USERS tablespace is lost due to a media failure. You notice that all the online redo logs have been overwritten sincethe last backup.  What would you do to recover the data file（）

• A、Take the USERS tablespace offline and re-create the lost data file.
• B、Shut down the instance， restore the data file from the last consistent backup， and restart the databaseinstance.
• C、Shut down the instance， restore all the database files from the last consistent backup， and restart thedatabase instance.
• D、Take the USERS tablespace offline， restore all the data files of the USERS tablespace from the lastconsistent backup， and make the tablespace online

第9题：

You work as a database administrator for Certkiller .com. Your database is in NOARCHIVELOG mode. The database has been configured with three redo logs groups， and there have been five log switches. You lost one non-system-critical data file from your database.  Which method would you use to recover the data file？（）

• A、Restore all the data files and open the database
• B、Create the data file and performtablespacerecovery
• C、No need to restore any file， just recover the database
• D、Restore only the system data file and recover the database
• E、Restore only lost date file and performtablespacerecovery

第10题：

The database is running in the ARCHIVELOG mode. It has three redo log groups with one member each. Oneof the redo log groups has become corrupted. You have issued the following command during the recovery of a damaged redo log file:ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 3; Which action should you perform immediately after using this command?（）

• A、You should perform a log switch
• B、You should make a backup of the database
• C、You should switch the database to the NONARCHIVELOG mode
• D、You should shut down the database instance and perform a complete database recovery