单选题You work as a database administrator for Supportcenter.cn. Your database is functional. One of the disks containing a mirrored redo log member has bad sectors in it. You are unable to fix the damaged file. How does the loss of a redo log member affect 

第1题：

Your database is in ARCHIVELOG mode. You have two online redo log groups, each of which contains one redo member. When you attempt to start the database, you receive the following errors: ORA-00313: open failed for members of log group 1 of thread 1 ORA-00312: online log 1 thread 1: 'D:/REDO01.LOG' You discover that the online redo log file of the current redo group is corrupted. Which statement should you use to resolve this issue?（）

• A、ALTER DATABASE DROP LOGFILE GROUP 1;
• B、ALTER DATABASE CLEAR LOGFILE GROUP 1;
• C、ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 1;
• D、ALTER DATABASE DROP LOGFILE MEMBER 'D:/REDO01.LOG

第2题：

You work as a database administrator for Certkiller .com. Your database is functional. One of the disks containing a mirrored redo log member has bad sectors in it. You are unable to fix the damaged file.  How does the loss of a redo log member affect the instance of the database that is currently running？（）

• A、The instance would normally abort.
• B、The instance would not be affected.
• C、The instance would be invalid， so would have to be aborted.
• D、The instance would remain open， but the LGWR process would fail.
• E、The instance would remain open and would automatically create the missing file

第3题：

第4题：

Your database is in ARCHIVELOG mode. You have two online redo log groups，each of which contains one redo member.  When you attempt to start the database， you receive the following errors：（）

• A、 ALTER DATABASE DROP LOGFILE GROUP 1
• B、 ALTER DATABASE CLEAR LOGFILE GROUP 1
• C、 ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 1
• D、 ALTER DATABASE DROP LOGFILE MEMBER ’D:///REDO01.LOG’

第5题：

In your database， online redo log files are multiplexed and one of the members in a group is lost due to media failure？ How would you recover the lost redo log member？（）

• A、 import the database from the last export
• B、 restore all the members in the group from the last backup
• C、 drop the lost member from the database and then add a new member to the group
• D、 restore all the database files from the backup and then perform a complete recovery
• E、 restore all the database files from the backup and then perform an incomplete recovery

第6题：

Redo log files are multiplexed in your database. The disk in which you have one of the redo log members is highly fragmented. In the process of defragmentation you lose the redo log member， which is not a member of the current group. How would you recover from the loss of the redo log member？（）

• A、SMON would automatically restore the lost file.
• B、You would need to restore the whole database from the last backup.
• C、You would need to restore the file from the last full database backup.
• D、You would need to use flashback technology to restore the lost redo log member.
• E、You would need to use Recovery Manager （RMAN） to restore the lost redo log member.
• F、You would need to restore the missing log file by copying one of the remaining files from the same group.

第7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8题：

第9题：

You work as a database administrator for Supportcenter.cn. Your database is functional. One of the disks containing a mirrored redo log member has bad sectors in it. You are unable to fix the damaged file. How does the loss of a redo log member affect the instance of the database that is currently running？（）

• A、The instance would normally abort.
• B、The instance would not be affected.
• C、The instance would be invalid， so would have to be aborted.
• D、The instance would remain open， but the LGWR process would fail.
• E、The instance would remain open and would automatically create the missing file

第10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.