Databases Reference
In-Depth Information
How It Works
The
test
command allows you to test drive the redo application process without making any permanent changes
to the data files. Running this command is particularly useful for diagnosing problems that you're having with the
application of redo during the recovery process. For example, you can use the
test
command with the
until
clause to
test up to a specific trouble point:
RMAN> recover database until time 'sysdate - 1/48' test;
RMAN> recover database until scn 2328888 test;
RMAN> recover database until sequence 343 test;
■
if you attempt to issue a
recover tablespace until ... test
, rman will attempt to perform
a tablespace point-in-time recovery (tSpitr).
Caution
If you're missing archived redo log files or online redo log files that are needed for recovery, you'll receive a
message similar to this:
ORA-06053: unable to perform media recovery because of missing log
If you can't locate the missing log, you'll most likely have to perform incomplete recovery. See Chapter 12 for
details on how to perform an incomplete recovery.
Performing Database-Level Recovery
Problem
You've lost all of your data files but still have your online redo log files. You want to perform complete recovery.
Solution
You can perform a complete database-level recovery in this situation with either the current control file or a backup
control file.
Use Current Control File
You must first put your database in mount mode to perform a database-wide restore and recovery. This is because the
system tablespace data file(s) must be offline when being restored and recovered. Oracle won't allow you to operate
your database in open mode with the system data file offline.
In this scenario, we simply start up the database in mount mode, issue the
restore
and
recover
commands, and
then open the database:
$ rman target /
RMAN> startup mount;
RMAN> restore database;
RMAN> recover database;
RMAN> alter database open;
