564.Your database has experienced a loss of datafile users_01.dbf, which is associated with a ablespace
called USERS. The database is still running. Which answer properly describes the rder of the steps that
you would use to recover from this error?
1. Shut down the database.
2. Take the users_01.dbf datafile offline with the alter database command.
3. Restore the users_01.dbf datafile from backup media with the required archived redo logs.
4. Restore all users tablespace-related datafiles from backup media.
5. Issue the recover tablespace users command.
6. Issue the recover datafile users_01.dbf command.
7. Start up the database.
8. Bring the users_01.dbf datafile online with the alter database command.
A.1, 3, 6, 7
B.2, 3, 6, 8
C.1, 2,3,6,7
D.1, 2, 3, 6, 7, 8
E.2, 3,6,5,7
Answer: B
答案解析：
参考：http://blog.csdn.net/rlhua/article/details/12622415
从题中得知，丢失了users01.dbf这个数据文件。因为users01.dbf不是关键数据文件，故可以offline来还原恢复。
恢复步骤为，先offline，在还原恢复，再online即可。
RMAN> repair failure;
Strategy: The repair includes complete media recovery with no data loss
Repair script: /u01/app/oracle/diag/rdbms/test0924/test0924/hm/reco_172511374.hm
contents of repair script:
# restore and recover datafile
sql 'alter database datafile 4 offline';
restore datafile 4;
recover datafile 4;
sql 'alter database datafile 4 online';