单选题You are managing Oracle Database 11g with an ASM storage with high redundancy. The following command was issued to drop the disks from the dga disk group after five hours：   ALTER DISKGROUP dga OFFLINE DISKS IN FAILGROUP f2 DROP AFTER 5H；   Which state

第1题：

How can you reverse the effects of an ALTER DISKGROUP ... DROP DISK command if it has alreadycompleted?（）

• A、Issue the ALTER DISKGROUP ... ADD DISK command.
• B、Issue the ALTER DISKGROUP ... UNDROP DISKS command.
• C、Issue the ALTER DISKGROUP ... DROP DISK CANCEL command.
• D、Retrieve the disk from the Recycle Bin after the operation completes

第2题：

You are managing an Oracle Database 11g ASM instance with a disk group dg01 having three disks. One of the disks in the disk group becomes unavailable because of power failure. You issued the following command to change the DISK_REPAIR_TIME attribute from 3.6 hours to 5 hours: ALTER DISKGROUP dg01 SET ATTRIBUTE 'disk_repair_time' = '5h'; To which disks in the disk group will the new value be applicable?（）

• A、all disks in the disk group
• B、all disks that are currently in OFFLINE mode
• C、all disks that are not currently in OFFLINE mode
• D、all disks in the disk group only if all of them are ONLINE

第3题：

第4题：

You are managing Oracle Database 11g with an ASM storage with high redundancy. The following command was issued to drop the disks from the dga disk group after five hours：   ALTER DISKGROUP dga OFFLINE DISKS IN FAILGROUP f2 DROP AFTER 5H；   Which statement is true in this scenario？（）

• A、 It starts the ASM fast mirror resync.
• B、 All the disks in the dga disk group would be OFFLINE and the DISK_REPAIR_TIME disk attribute would be set to 5 hours.
• C、 It drops all disk paths from the dga disk group.
• D、 All the disks in the dga disk group in failure group f2 would be OFFLINE and the DISK_REPAIR_TIME disk attribute would be set to 5 hours.

第5题：

You just issued the following statement: ALTER TABLE SALES DROP COLUMN PROFIT. Which of the following choices identifies when the column will actually be removed from Oracle?（）

• A、Immediately following statement execution 
• B、After the ALTER TABLE DROP UNUSED COLUMNS command is issued 
• C、After the ALTER TABLE SET UNUSED COLUMN command is issued 
• D、After the ALTER TABLE MODIFY command is issued

第6题：

What is the net effect of the following command？（）   alter diskgroup dgroup1 drop disk abc；

• A、 The disk ABC will be dropped from the disk group. Since you did not issue a rebalance command，the data on that disk will be lost.
• B、 The command will raise an error indicating that you need to rebalance the disk group to remove the data from that disk prior to dropping the disk.
• C、 The disk group will be automatically rebalanced during the drop operation. Once the rebalancing is complete，the disk will be dropped.
• D、 This command will fail because you cannot drop a specific disk in an ASM disk group.
• E、 The disk drop command will be suspended for a predetermined amount of time，waiting for you to also issue an alter diskgroup rebalance command. Once you have issued the rebalance command，ASM will proceed to rebalance the disk group and then drop the disk.

第7题：

After executing the command alter diskgroup disk group2 drop disk dg2a； you issue the following command from the ASM instance：   Select group_number， count（*） from v$asm_operation；   What is the implication if the query against V$ASM_OPERATION returns zero rows？（）  

• A、 The drop disk operation is still proceeding and you cannot yet run the undrop disks operation.
• B、 The drop disk operation is complete and you can run the undrop disks command if needed.
• C、 The drop disk operation is complete and you cannot run the undrop disk command.
• D、 The query will fail since there is not a V$ASM_OPERATION view available in an ASM instance. 
• E、 None of the above is true.

第8题：

第9题：

You are managing an ASM instance. You previously issued the following statements: ALTER DISKGROUP dg1 DROP DISK disk2; ALTER DISKGROUP dg1 DROP DISK disk3; ALTER DISKGROUP dg1 DROP DISK disk5; You want to cancel the disk drops that are pending for the DG1 disk group. Which statement should you issue?（）

• A、ALTER DISKGROUP dg1 UNDROP disk2, disk3, disk5;
• B、ALTER DISKGROUP dg1 UNDROP;
• C、ALTER DISKGROUP dg1 UNDROP DISKS;
• D、You cannot cancel the pending disk drops.

第10题：

Examine the following ALTER command: SQL> ALTER DISKGROUP dgroup1 UNDROP DISKS; What is the purpose of the command?（）

• A、It cancels all pending disk drops within the disk group.
• B、It restores disks that are being dropped as the result of a DROP DISKGROUP operation
• C、It mounts disks in the disk group for which the drop-disk operation has already been co pleted
• D、It restores all the dropped disks in the disk group for which the drop-disk operation has already been completed
• E、It adds previously dropped disks back into the disk group