Databases Reference
In-Depth Information
This prior command does not actually restore any files, it just allows you a way to preview which files will be
required for a recovery operation.
How It Works
You can run a
restore ... preview
for any
restore
command. For example, all of the following are valid:
RMAN> restore database preview;
RMAN> restore database from tag TAG20120722T203338 preview;
RMAN> restore datafile 1, 2, 3, 4 preview;
RMAN> restore archivelog all preview;
RMAN> restore archivelog from time 'sysdate - 1' preview;
RMAN> restore archivelog from scn 850000 preview;
RMAN> restore archivelog from sequence 29 preview;
When you use the
preview
command, no data files are actually restored. The
restore ... preview
command
queries the RMAN repository to report which backup pieces and archive redo logs will be needed for the specified
restore and recovery operation. It does not check to see whether the RMAN backup files physically exist or verify they
are accessible.
You can preview output in the normal verbose mode, or you can have it summarized. This summary mode will
reduce the lengthy output. Here are some examples:
RMAN> restore tablespace users preview summary;
RMAN> restore database preview summary;
If you use a media manager that supports vaulted backups, you can use
preview recall
to recall media from
remote storage. This next example will request that any media needed to restore the database be recalled from remote
storage.
RMAN> restore database preview recall;
Verifying Integrity of Backup Files
Problem
You need to perform a restore and recovery, but first you want to validate only that the backup pieces are available and
structurally sound before restoring data files.
Solution
You can use either the
restore ... validate
or the
validate
command to verify the availability and integrity of
backup files required by RMAN to perform the restore operation. These commands do not restore any files; rather,
they check the soundness of the files that would be used to do a restore.
