Which option identifies the correct sequence that you must use to recover the data files?

Your production database is running in archivelog mode and you are using recovery manager (RMAN) with recovery catalog to perform the database backup at regular intervals. When you attempt to restart the database instance after a regular maintenance task on Sunday, the database fails to open displaying the message that the data file belonging to the users tablespace are corrupted.
The steps to recover the damaged data files are follows:
1. Mount the database
2. Open the database
3. Recover the data file
4. Restore the data file
5. Make the data file offline
6. Make the data file online
Which option identifies the correct sequence that you must use to recover the data files?

A.
2, 4, 3

B.
1, 4, 3, 2

C.
2, 5, 4, 3, 6

D.
5, 2, 4, 3, 6

E.
1, 5, 4, 3, 6, 2

Explanation:
http://ss64.com/ora/rman_recover.html
Steps for Media Recovery:
1. Mount or open the database.
Mount the database when performing whole database recovery,
or open the database when performing online tablespace recovery.
2. To perform incomplete recovery,
use the SET UNTIL command to specify the time,
SCN, or log sequence number at which recovery terminates.
Alternatively, specify the UNTIL clause on the RESTORE and RECOVER commands.
3. Restore the necessary files with the RESTORE command.
4. Recover the datafiles with the RECOVER command.
5. Place the database in its normal state.
For example, open it or bring recovered tablespaces online.
Restore and recover a datafile
RMAN> SQL ‘ALTER DATABASE DATAFILE 64 OFFLINE’;
RMAN> RESTORE DATAFILE 64;
RMAN> RECOVER DATAFILE 64;
RMAN> SQL ‘ALTER DATABASE DATAFILE 64 ONLINE’;

Show Hint

← Previous question

Chien-Hung Lin

you could not offline tablespace only on mount status.
the correct answer should be “B.1, 4, 3, 2”

djeday84

wrong =) offline datafiles are possoble

and answer is also wrong =)

D. 5, 2, 4, 3, 6
5. Make the data file offline
2. Open the database
4. Restore the data file
3. Recover the data file
6. Make the data file online

SQL> startup;
ORACLE instance started.
………..
Database mounted.
ORA-01157: cannot identify/lock data file 4 – see DBWR trace file
ORA-01110: data file 4: ‘+DATA/orcl/datafile/users.259.809884355’

[oracle@oel5-1 ~]$ rman target / catalog rcat/passwd@rac

5 ) RMAN> sql ‘alter database datafile 4 offline ‘;
sql statement: alter database datafile 4 offline

2 ) RMAN> alter database open;
database opened

4 ) RMAN> restore datafile 4;
………..
channel ORA_DISK_1: restore complete, elapsed time: 00:00:07
Finished restore at 12-MAR-13
starting full resync of recovery catalog
full resync complete

3 ) RMAN> recover datafile 4;
..
6 ) RMAN> sql ‘alter database datafile 4 online ‘;

sql statement: alter database datafile 4 online

Bingo. We got Minimal downtime

iimax

the answer is correct.because of file lost, you cannot startup the database.mount first,then issue offline -> restore –> recover –> online command

djeday84

“because of file lost, you cannot startup the database”
really ?!

When you attempt to restart the database instance after a regular maintenance task on Sunday, the database fails to open displaying the message that the data file belonging to the users tablespace are corrupted.

ok, startup db ( failed to start diplaying message )
SQL> startup;
ORACLE instance started.
………..
Database mounted.
ORA-01157: cannot identify/lock data file 4 – see DBWR trace file
ORA-01110: data file 4: ‘+DATA/orcl/datafile/users.259.809884355′

now db is mount
this allow us to make datafile ( not system or undo ) to go offline and do our job

any way there is no sens in answer E, if use this logic then B is more acceptable

iimax

thanks for your reply,you’re right.datafile lost,but db is already in mount state.

Justyna

but in B you miss putting a file offline what you say yourself should be done after database is mounted.