单选题You have lost datafiles 1 and 3 from your database，and the database has crashed.  In what order should you perform the following steps to recover your database？（） 1. Take the datafiles that were lost offline.  2. startup mount the database  3. Issue th

第1题：

You are working on the PROD database， which is in NOARCHIVELOG mode. You lost the active online redo log group due to a media failure. How should you recover your database？（）

• A、 Restore the database from a whole consistent backup and start the database in MOUNT mode. Then， open the database with the RESETLOGS option after performing a cancel-based recovery.
• B、 Restore the database from a whole consistent backup and start the database in MOUNT mode. Then， drop the lost redo log group and open the database with the RESETLOGS option after performing a cancel-based recovery.
• C、 Restore the database from a whole consistent backup and start the database in MOUNT mode. Then， clear the lost redo log group and open the database with the RESETLOGS option after performing a cancel-based recovery.
• D、 Do nothing. You do not need to recover the database in this case； an instance recovery will be performed by the SMON process on startup.

第2题：

A user sends you an email with the following error message： create table idtable（id number） * ERROR at line  1： ORA- 01110： data file 4： ，，/oracle01/oradata/orcl/users01.dbf ORA-27041： 01116： error in opening database file 4 ORA-unable to open file Linux Error：  2： No such file or directory Additional information：  3 You can choose from the following steps： a. Restore the missing database datafiles.  b. Take the missing datafile offline.  c. Shut down the database.  d. Issue the recover tablespace USERS command.  e. Issue the Startup Mount command to mount the database. f. Bring the USERS tablespace online.  g. Issue the alter database open command.  Which is the correct order of these steps in this case？（）

• A、b， a， d， f
• B、c， a， e， b， d， f， g
• C、c， e， d， g
• D、b， d， f 
• E、e， d， g

第3题：

第4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5题：

You have lost all your SYSTEM tablespace datafiles （system_01.dbf and system_02.dbf） nd the database has crashed.  What would be the appropriate order of operations to correct the situation？（）   a. Mount the database with the startup mount command.  b. Take the SYSTEM datafile offline with the alter database command.  c. Restore the SYSTEM_01.dbf datafile from backup media with the required archived redo logs.  d. Restore all SYSTEM tablespace-related datafiles from backup media. e. Issue the recover tablespace SYSTEM command.  f. Issue the recover datafile SYSTEM_01.dbf command.  g. Open the database with the alter database open command.  h. Open the database with the alter database open resetlogs command.

• A、a， c， f， g
• B、b， d， e， h
• C、a， b， c， f， g
• D、d， a， e， g
• E、b， c， f， e， g

第6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7题：

Your database is in NOARCHIVELOG mode. You start to do a backup， but your users complain that they dont want you to shut down the database to perform the backup. What options are available to you？（）  

• A、 Put the database in hot backup mode and perform an online backup，including backing up the  archived redo logs.
• B、 Just back up the database datafiles without shutting down the database.
• C、 You will have to wait until you can shut down the database to perform the backup.
• D、 Mark each datafile as backup in progress， back them up individually，and then mark them as backup not in progress. No archived redo logs will need to be backed up.
• E、 Only back up the datafiles that the user will not be touching. Once the user has finished what they were doing，you can shut down the database and back up the datafiles the user changed during the  course of the remaining backup

第8题：

At database startup， you discover that one of the disks containing an index tablespace has been lost due to a media failure. A backup of the lost index tablespace is not available. You have all the necessary scripts to recreate the indexes. You need to re-create the indexes in a new index tablespace. Which action must you perform before re-creating the indexes？（）

• A、 Start the database in OPEN mode， and create a new index tablespace.
• B、 Start the database in OPEN mode， and drop the lost index tablespace from the database.
• C、Start the database in MOUNT mode， create a new index tablespace， and drop the lost index tablespace from the database.
• D、 Start the database in MOUNT mode， drop the lost index tablespace from the database， open the database， and create a new index tablespace.

第9题：

You executed the STARTUP MOUNT command to start your database. For which database operation do you need to start the database in the MOUNT state？（）

• A、renaming the control files
• B、dropping a user in your database
• C、enabling or disabling redo log archiving
• D、dropping a tablespace in your database
• E、re-creating the control files， after you lost all the control files in your database

第10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 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 perform tablespace recovery
• 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