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Oracle® Database Backup and Recovery Reference
10g Release 2 (10.2)

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The RECOVER command has three distinct uses:

When performing media recovery, RMAN first looks for archived logs on disk, and if none are available, then it restores logs from backups to the LOG_ARCHIVE_DEST_1 destination (or the SET ARCHIVELOG DESTINATION) as needed for the recovery.

Complete and point-in-time recovery of a database can use both incremental backups and archived logs. If RMAN has a choice between applying an incremental backup or applying redo, then it always chooses the incremental backup. Applying incremental backups is faster and captures NOLOGGING changes. If overlapping levels of incremental backup are available, then RMAN automatically chooses the one covering the longest period of time.

RMAN also applies incremental backups to restored files that were not restored from an incremental backup.


When RMAN applies incremental backups, it also recovers changes to objects created with the NOLOGGING option. Applying archived redo logs to datafiles does not recover these changes.

See Also:

  • Oracle Database Backup and Recovery Basics to learn how to recover datafiles.

  • "RESTORE" command for explanation of the default location for restoring archived logs. Note that RMAN automatically specifies the MAXSIZE option when staging logs in the flash recovery area.

Restrictions and Usage Notes

Keywords and Parameters


Syntax Element Description
DEVICE TYPE deviceSpecifier Allocates automatic channels for the specified device type only. For example, if you configure automatic disk and tape channels, and issue RECOVERDEVICE TYPE DISK..., then RMAN allocates only disk channels.

See Also: "deviceSpecifier"


Syntax Element Description
COPY OF Applies incremental backups to the specified image copy to roll it forward to any time equal to or before the most recent incremental backup of the file. The existing image copy is overwritten, and remains in a fuzzy state during the recovery. RECOVER COPY is a method for updating a copy and is not a media recovery of a current database file. This command is meant to be used in conjunction with the BACKUP... FOR RECOVER OF COPY syntax, to implement a strategy using incrementally updated backups.

The following requirements must be met:

  • At least one copy of each datafile that you are recovering must exist.

  • Incremental backups taken after the image copy that you are recovering must exist.

RMAN selects one suitable copy if there are multiple possible copies to which the incrementals can be applied to carry out the operation.

Note: RMAN issues a warning (not an error) if it cannot recover to the specified time (or current time if none is specified) because no incrementals are available.

WITH TAG 'tag_name' Specifies a tag name to identify the image copy to be rolled forward.
DATAFILECOPY Applies incremental backups to the specified datafile image copy. Refer to description of RECOVER COPY OF..
SKIP [FOREVER] TABLESPACE Specifies tablespaces that should not be recovered, which is useful for avoiding recovery of tablespaces containing only temporary data or for postponing recovery of some tablespaces. The SKIP clause takes the datafiles in the specified tablespaces offline before starting media recovery. These files are left offline after the media recovery is complete.

If you perform incomplete recovery, then SKIP is not allowed. Instead, use SKIP FOREVER, with the intention of dropping the skipped tablespaces after opening the database with the RESETLOGS option. The SKIP FOREVER clause causes RMAN to take the datafiles offline with the DROP option. Only use SKIP FOREVER when the specified tablespaces will be dropped after opening the database.

untilClause Specifies a past time, SCN, or log sequence number for termination of the RECOVER command. When used with one or more tablespaces, indicates a TSPITR operation for the named tablespaces. It cannot be used with RECOVER DATAFILE. It should not be used for RECOVER DATABASE (see "Restrictions and Usage Notes" for details). After DBPITR, you must open the database with the RESETLOGS option.

See Also: "untilClause"


Syntax Element Description
DATABASE Specifies that the entire database is to be recovered. By default, RMAN performs complete recovery. For incomplete recovery, specify an untilClause.
DATAFILE datafileSpec Specifies a list of one or more datafiles to recover. Specify datafiles by either filename (by using a quoted string) or absolute datafile number (by using an integer).

If you are using the control file as the exclusive repository for RMAN metadata, then the filename must be the name of the datafile as recorded in the control file.

If you are using a recovery catalog, then the filename of the datafile must be the most recent name recorded in the catalog, even if the name in the control file has been updated more recently. For example, assume that a datafile was renamed in the control file. The instance then fails before you can resynchronize the catalog. Specify the old name of the datafile in the RECOVER command, because this is the name recorded in the catalog.

See Also: "datafileSpec"

TABLESPACE 'tablespace_name' Specifies tablespaces by tablespace name.


Syntax Element Description
recoverOptionList Specifies various recovery options.
ARCHIVELOG TAG = tag_name Specifies the tag for an archived log backup to be used during recovery. If the tagged backup does not contain all the necessary logs for recovery, RMAN uses logs or incremental backups as needed from whatever is available. Note that tag names are not case sensitive and display in all uppercase.
AUXILIARY DESTINATION [ = ] 'location' Can only be used when performing TSPITR. Used to automate the management of auxiliary set files during TSPITR. Specifies a location where auxiliary set datafiles, control files and online logs are created during TSPITR if another location for an individual file is not explicitly specified.

If you do not specify AUXILIARY DESTINATION for a TSPITR, then you must specify the naming of individual auxiliary set datafiles, control files, and online logs before executing the RECOVER TABLESPACE... UNTIL... command. Otherwise, TSPITR will fail.

See also: The chapter on TSPITR in Oracle Database Backup and Recovery Advanced User's Guide for more details about the auxiliary destination.

CHECK LOGICAL Tests data and index blocks that pass physical corruption checks for logical corruption, for example, corruption of a row piece or index entry. If RMAN finds logical corruption, it logs the block in the alert.log and server session trace file.

The MAXCORRUPT setting represents the total number of physical and logical corruptions permitted on a file. By default, MAXCORRUPT is 0, so that if there are any corrupt blocks, media recovery fails. If recovery including corrupt blocks is permissible, then set MAXCORRUPT to the smallest number of corrupt blocks that causes media recovery to fail. For example, to tolerate one corrupt block, set MAXCORRUPT to 1.

If the total number of physical and logical corruptions detected for a file is less than its MAXCORRUPT setting, then the RMAN command completes and the database populates V$DATABASE_BLOCK_CORRUPTION with corrupt block ranges. Otherwise, the command terminates without populating V$DATABASE_BLOCK_CORRUPTION.

CHECK READONLY Checks the headers of read-only files to ensure that they are current before omitting them from the recovery.
DELETE ARCHIVELOG [MAXSIZE integer [K|M|G]] Deletes archived logs restored from backups or copies that are no longer needed. RMAN does not delete archived logs that were already on disk before the RESTORE command started.

If you do not specify MAXSIZE, then RMAN deletes restored archived logs as they are applied. If you specify MAXSIZE, then RMAN will not use more than integer amount of disk space for restored archived logs. If recovery requires the restore of a log larger than the MAXSIZE value, then RMAN reports an error indicating that you should increase the MAXSIZE value. If MAXSIZE is smaller than the backup set containing the logs, then RMAN must read the backup set more than once to extract the logs. In this situation, RMAN issues a warning that MAXSIZE should be increased.

Note: If archived redo logs are restored to the flash recovery area then the DELETE ARCHIVELOG option is enabled by default.

FROM TAG = tag_name Specifies the tag for an incremental backup to be used during recovery. If the tagged backup does not contain all the necessary incrementals for recovery, then RMAN uses logs or incremental backups as needed from whatever is available. Note that tag names are not case sensitive and display in all uppercase.

See Also: "BACKUP" to learn how a tag can be applied to an individual copy of a duplexed backup set, and to learn about the default filename format for backup tags

NOREDO Suppresses the application of redo logs during recovery. Only incremental backups are applied.

One use of this option is in updating full backups of NOARCHIVELOG databases by using incremental backups. If you do not specify NOREDO when recovering a NOARCHIVELOG database, then the database terminates recovery and issues an error.

Note: Incremental backups of NOARCHIVELOG databases can only be taken after a consistent shutdown.

Another use is in updating standby or duplicate databases. Incremental backups created with the BACKUP INCREMENTAL FROM SCN command can be applied at the standby or duplicate database. This process is described in Oracle Database Backup and Recovery Advanced User's Guide.

TEST Use the TEST clause to conduct a trial recovery. A trial recovery is useful if a normal recovery procedure has encountered some problem. It lets you look ahead into the redo stream to detect possible additional problems. The trial recovery applies redo in a way similar to normal recovery, but it does not write changes to disk, and it rolls back its changes at the end of the trial recovery.

Note: You can use this clause only if you have restored a backup taken since the last RESETLOGS operation. Otherwise, the database returns an error.


During TSPITR, RMAN needs information about which tablespaces had undo segments at the TSPITR target time. This information is usually available in the recovery catalog, if one is used.

If there is no recovery catalog, or if the information is not found in the recovery catalog, RMAN proceeds assuming that the set of tablespaces with undo segments at the target time is the same as the set of tablespaces with undo segments at the present time. If this assumption is not correct, TSPITR fails with an error. In such a case, use this clause to provide a list of tablespaces with undo segments at the target time.

ALLOW integer CORRUPTION The ALLOW integer CORRUPTION clause lets you specify, in the event of logfile corruption, the number of corrupt blocks that can be tolerated while allowing recovery to proceed.

When you use this clause during trial recovery (that is, in conjunction with the TEST clause), integer can exceed 1. When using this clause during normal recovery, integer can only be 0 or 1.

NOPARALLEL Specifies not to perform recovery in parallel. Parallel execution is the default for RECOVER.
PARALLEL [integer] Specifies to perform recovery in parallel (the default).

By default, the database determines the optimal degree of parallelism, which is the number of parallel threads used in the recovery operation. It is generally not necessary for you to specify the degree of parallelism. However, you can specify the degree of parallelism directly by including the integer in the PARALLEL clause. Each parallel thread may use one or two parallel execution servers.

For more complete information on PARALLEL, see the description of the PARALLEL clause in the discussion of CREATE TABLE in Oracle Database SQL Reference.


Recovering a Tablespace in an Open Database: Example The following example takes tablespace tools offline, uses automatic channels to restore and recover it (deleting the logs that it restored from tape), then brings it back online:

# restore only 2M of logs at a time, then delete them

Recovering Datafiles Restored to New Locations: Example The following example uses the preconfigured disk channel and manually allocates one media management channel to use datafile copies on disk and backups on tape, and restores one of the datafiles in tablespace users to a different location:

  SET NEWNAME FOR DATAFILE '?/oradata/trgt/users01.dbf' 
    TO '/tmp/users01.dbf';

Performing DBPITR with a Backup Control File and Recovery Catalog: Example Assume that all datafiles and control files as well as archived redo log 40 were lost due to a disk failure. Also assume that you do not have incremental backups. You need to recover the database with available archived redo logs. You do not need to restore tablespace history because it has not changed since log 40. After connecting to the target and recovery catalog, follow the example shown here:

  SET UNTIL SEQUENCE 40 THREAD 1;      # Recover database until log sequence 40 

If the database uses locally-managed temporary tablespaces, and you restore a backup control file, and you do not have a recovery catalog, then you must add tempfiles to these tablespaces afterwards, using the SQL ALTER TABLESPACE... ADD TEMPFILE command:

RMAN> SQL "ALTER TABLESPACE temp ADD TEMPFILE ''?/oradata/trgt/temp01.dbf'' REUSE";

RECOVER an Image Copy of a Datafile to a Point in Time: Example Assume that you have an image copy backup of a datafile and you want to roll it forward in time using incremental backups. Use RECOVER DATAFILECOPY with the UNTIL TIME option. For example, run the following command:


Available incremental backups are applied to the datafile copy to recover it to the desired point in time. Redo from the archived redo logs is not applied by this command.