Database Reference
In-Depth Information
Performing Log Sequence-Based Recovery
Usually this type of incomplete database recovery is initiated because you have a missing or damaged archived redo
log file. If that's the case, you can recover only up to your last good archived redo log file, because you can't skip a
missing archived redo log.
How you determine which archived redo log file to restore up to (but not including) will vary. For example, if you
are physically missing an archived redo log file, and RMAN can't find it in a backup set, you'll receive a message such
as this when trying to apply the missing file:
RMAN-06053: unable to perform media recovery because of missing log
RMAN-06025: no backup of archived log for thread 1 with sequence 19...
Based on the previous error message, you would restore up to (but not including) log sequence 19.
$ rman target /
RMAN> startup mount;
RMAN> restore database until sequence 19;
RMAN> recover database until sequence 19;
RMAN> alter database open resetlogs;
If successful, you should see output such as this:
Statement processed
■
Log sequence-based recovery is similar to user-managed cancel-based recovery. see Chapter 3 for details on
a user-managed cancel-based recovery.
Note
Performing SCN-Based Recovery
SCN-based incomplete database recovery works in situations in which you know the SCN value at which you want
to end the restore-and-recovery session. RMAN will recover up to, but not including, the specified SCN. RMAN
automatically terminates the restore process when it reaches the specified SCN.
You can view your database SCN information in several ways:
•
Using LogMiner to determine an SCN associated with a DDL or DML statement
alert.log
file
•
Looking in the
•
Looking in your trace files
FIRST_CHANGE#
column of
V$LOG
,
V$LOG_HISTORY
and
V$ARCHIVED_LOG
After establishing the SCN to which you want to restore, use the
UNTIL SCN
clause to restore up to, but not including,
the SCN specified. The following example restores all transactions that have an SCN that is less than 95019865425:
•
Querying the
$ rman target /
RMAN> startup mount;
RMAN> restore database until scn 95019865425;
RMAN> recover database until scn 95019865425;
RMAN> alter database open resetlogs;
If everything goes well, you should see output such as this:
Statement processed
