单选题You have only two redo log groups and these groups get overwritten several times in a day. Your database operates in NOARCHIVELOG mode and user-managed consistent backups are performed every Sunday night. On Thursday morning， you find that an important

第1题：

Your production database is running in the ARCHIVELOG mode and the ARCn process is functional. You have two online redo log groups. Which three background processes would be involved when a log switch happens？ （）

• A、archival
• B、log writer
• C、database writer
• D、system monitor
• E、process monitor
• F、change tracking writer

第2题：

Which two statements are true regarding the database in ARCHIVELOG mode？（）

• A、You have to shut down the database to perform the backups.
• B、Archiving information is written to the data files and redo log files.
• C、You can perform complete database backups without closing the database.
• D、Online redo log files have to be multiplexed before putting the database in ARCHIVELOG mode.
• E、All the previous database backups become invalid after you configure the database to ARCHIVELOG mode.

第3题：

You have only two redo log groups and these groups get overwritten several times in a day. Your database operates in NOARCHIVELOG mode and user-managed consistent backups are performed every Sunday night. On Thursday morning， you find that an important table has been dropped and purged. With reference to this scenario， up to what point in time can the data be recovered？（）

• A、 until Thursday morning
• B、 until that point in time when the database is opened
• C、 until that point in time when the recovery is performed
• D、 until last Sunday’s backup
• E、 until that point in time when the table is dropped and purged
• F、 until Wednesday evening

第4题：

In your production database， you have observed that the database server performance degrades whenever there is a switch between the log groups. On further investigation， you find that the database is running in ARCHIVELOG mode and the archived log files are being written to the same disk that is used to store the redo log members.  Which two actions would you take to improve the performance of the database server？ （）

• A、increase the size of the redo log buffer
• B、increase the number of redo log groups
• C、increase the number of log writer processes
• D、increase the number of ARCn processes
• E、change the appropriate LOG_ARCHIVE_DEST_n parameter to place the archived log files in a separate location

第5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6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7题：

In which two cases would you perform only consistent backup？（）

• A、You are working on a database where downtime is not tolerated.
• B、You are working on a database where downtime can be tolerated.
• C、You are working on a database that operates in ARCHIVELOG mode.
• D、You are working on a database that operates in NOARCHIVELOG mode.
• E、You are working on a database where all the tablespaces are locally managed.
• F、You are working on a database where control files and redo log files are multiplexed.
• G、You are working on a database where control files and redo log files are not multiplexed.

第8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9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10题：

Which two requirements are critically important to implement for your database backup strategy if you require a 24 hours a day， 7 days a week production environment？（）

• A、ARCHIVELOG mode.
• B、NOARCHIVELOG mode.
• C、Open database backups.
• D、Consistent whole backups.