单选题You work as a database administrator for Supportcenter.cn. On a Monday morning， you find the database instance aborted. After inspecting the alert log file， you execute the STARTUP command in SQL*Plus to bring the instance up. What statement is true？（）

第1题：

You work as a database administrator for Supportcenter.cn. You added atablespaceto your database. Because of the changes to the physical structure of your database， you performed a backup of the control file to trace. After this， you lost only the control files and the instance aborted due to a hardware failure. How would you proceed to recover the database？（）

• A、Start the instance and open the database， instance recovery automatically recoverscontrol files
• B、Create a file based on the contents of the trace file and save it to the control file locations and start the database
• C、Re-create the database （The recovery of the control file is not possible because you have lost all the control files.）
• D、Start the instance， in the NOMOUNTstate，re-create the control file using the CREATE CONTROLFILE command stored in the trace file.
• E、Start the instance and MOUNT the database， then re-create the control file using the CREATE CONTROLFILE command stored in the trace file.

第2题：

You work as a database administrator for Supportcenter.cn. Your database is opened inNOARCHIVEKLOG mode. You decide to place the database in ARCHIVELOG mode. How would you do this？（）

• A、Execute the ALTER DATABASE ARCHIVELOG statement
• B、Select ARCHIVELOG option in the database control and restart the database to apply the changes.
• C、Shut down and start the instance， and in the NOMOUNT state execute the ALTER DATABASE ARCHIVELOG statement.
• D、Shut down and start the instance， mount the database， then execute the ALTER DATABASE ARCHIVELOG statement.

第3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4题：

You work as a database administrator for Certkiller .com. You added atablespaceto your database. Because of the changes to the physical structure of your database， you performed a backup of the control file to trace. After this， you lost only the control files and the instance aborted due to a hardware failure.  How would you proceed to recover the database？（）

• A、Start the instance and open the database, instance recovery automatically recovers control files 
• B、Create a file based on the contents of the trace file and save it to the control file locations and start the database 
• C、Re-create the database (The recovery of the control file is not possible because you have lost all the control files.) 
• D、Start the instance, in the NOMOUNTstate,re-create the control file using the CREATE CONTROLFILE command stored in the trace file. 
• E、Start the instance and MOUNT the database, then re-create the control file using the CREATE CONTROLFILE command stored in the trace file.

第5题：

You work as a database administrator for Certkiller .com. On a Monday morning， you find the database instance aborted. After inspecting the alert log file， you execute the STARTUP command in SQL*Plus to bring the instance up. What statement is true？（）

• A、PMON coordinates media recovery.
• B、SMON coordinates instance recovery.
• C、PMON coordinates instance recovery.
• D、Undo Advisor would roll back all uncommitted transactions.
• E、SQL*PLUS reports an error with the message asking you to perform instance recovery. 

第6题：

After performing a clean shut down of the database instance for maintenance， you mount thedatabase and then execute a command to open the database： SQL> ALTER DATABASE OPEN；  Which two statements are true（）

• A、The online redo log files and online data files are opened.
• B、All the online data file headers are checked for consistency.
• C、Instance recovery is performed before opening the database.
• D、The path and existence of all the log file members are checked

第7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8题：

After performing a clean shut down of the database instance for maintenance， you mount the database andthen execute a command to open the database：SQL> ALTER DATABASE OPEN； Which two statements are true（）

• A、The online redo log files and online data files are opened.
• B、All the online data file headers are checked for consistency.
• C、Instance recovery is performed before opening the database.
• D、The path and existence of all the log file members are checked

第9题：

You work as a database administrator for Certkiller .com. Your database is opened in NOARCHIVEKLOG mode. You decide to place the database in ARCHIVELOG mode.  How would you do this？（）

• A、Execute the ALTER DATABASE ARCHIVELOG statement 
• B、Select ARCHIVELOG option in the database control and restart the database to apply the changes. 
• C、Shut down and start the instance, and in the NOMOUNT state execute the ALTER DATABASE ARCHIVELOG statement. 
• D、Shut down and start the instance, mount the database, then execute the ALTER DATABASE ARCHIVELOG statement. 

第10题：

You work as a database administrator for Supportcenter.cn. Your database is in the MOUNT state and you execute the following command to open it ALTER DATABASE OPEN； What two actions are performed as a result of this command？（）

• A、All control files are opened
• B、All redo files are opened
• C、The password file is opened
• D、The parameter file is opened
• E、All online data files are opened