OCP-1Z0-053-200题-49题-627

QUESTION 49

In Recovery Manager (RMAN), you are taking image copies of the data files of your production database and

rolling them forward at regular intervals. You attempt to restart your database. After a regular maintenance

task, you realize that one of the data files that belongs to the USERS tablespace is damaged and you needto

recover the data file by using the image copy. Because a media failure caused the data file to be damaged,

you want to place the data file in a different location while restoring the file. Which option must you consider for

this task?

A. using only the RMAN SWITCH command to set the new location for the data file

B. placing the database in the MOUNT state for the restore and recovery operations.

C. using an RMAN RUN block with the SET NEWNAME and then the SWITCH command.

D. configuring two channels: one for the restore operation and the other for the recovery operation

Answer: C

同627题：http://blog.youkuaiyun.com/rlhua/article/details/17260407

Explanation/Reference:

Section: Backup, Recovery & Recovery Manager (RMAN)

Explanation/Reference:

http://download.oracle.com/docs/cd/B10501_01/server.920/a96566/rcmconc2.htm

RMAN automates the procedure for restoring files. Youdo not need to go into the operating system, locate the

backup or copy that you want to use, and manually copy files into the appropriate directories. When you issue

a RESTOREcommand, RMAN directs a server session to restore the correct backups and copies to either:

The default location, overwriting the files with the same name currently there

A new location, which you can specify with the SET NEWNAMEcommand

To restore a datafile, either mount the database orkeep it open and take the datafile to be restored offline.

When RMAN performs a restore, the RESTOREcommand creates the restored files as datafile copies and

records them in the repository. The following tabledescribes the behavior of the RESTORE, SET NEWNAME, and

SWITCHcommands.

For example, if you restore datafile ?/oradata/trgt/tools01.dbfto its default location, then RMAN

restores the file ?/oradata/trgt/tools01.dbfand overwrites any file that it finds with the same filename.

If you run a SET NEWNAMEcommand before you restore a file, then RMAN creates a datafile copy with the

name that you specify. For example, assume that yourun the following commands:

SET NEWNAME FOR DATAFILE '?/oradata/trgt/tools01.dbf' TO '/tmp/tools01.dbf';

RESTORE DATAFILE '?/oradata/trgt/tools01.dbf';

In this case, RMAN creates a datafile copy of ?/oradata/trgt/tools01.dbfnamed /tmp/tools01.dbf

and records it in the repository.

To change the name for datafile ?/oradata/trgt/tools01.dbfto /tmp/tools01.dbfin the control file,

run a SWITCHcommand so that RMAN considers the restored file asthe current database file. For example:

SWITCH DATAFILE '/tmp/tools01.dbf' TO DATAFILECOPY '?/oradata/trgt/tools01.dbf';

The SWITCHcommand is equivalent to the SQL statement ALTER DATABASE RENAME FILE.