Your database is functioning in ARCHIVELOG mode. In which two situations would you perform a cancel-based recovery？ （）A、 You find that one of the redo log members in each redo log group is lost.B、 You find that a data file that belongs to the USERS tables

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：

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3题：

第4题：

Which statement about recovering from the loss of a redo log group is true?（）

• A、If the lost redo log group is ACTIVE, you should first attempt to clear the log file.
• B、If the lost redo log group is CURRENT, you must clear the log file.
• C、If the lost redo log group is ACTIVE, you must restore, perform cancel-based incomplete recovery, and open the database using the RESETLOGS option.
• D、If the lost redo log group is CURRENT, you must restore, perform cancel-based incomplete recovery, and open the database using the RESETLOGS option.

第5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：

You are maintaining your OLTP database in Oracle10g. While observing the performance of the database， you find that the log switch occurs more than once for every 20 minutes， affecting the database performance. Which factor is responsible for frequent log switches？（）  

• A、the value of the UNDO_RETENTION initialization parameter
• B、the value of the optimal redo log file size provided by the Redo Logfile Size Advisor
• C、the online redo log files size
• D、the number of redo log members in a group

第8题：

第9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