RESTORE

Syntax

restore::=

Text description of restore

restoreObject::=

Text description of restoreObject

restoreSpecOperand::=

Text description of restoreSpecOperand

autoBackupOptList::=

Text description of autoBackupOptList

Purpose

The primary use of RESTORE is to restore files from backups or image copies. Typically, you restore when a media failure has damaged a current datafile, control file, or archived log or prior to performing a point-in-time recovery.

There are two other uses of RESTORE:

RESTORE... PREVIEW identifies the backups which RMAN will use to perform any RESTORE operation. Output from a RESTORE... PREVIEW is in the same format as the output of the LIST command.
With the VALIDATE option, RMAN scans existing backups that it would use to perform a RESTORE operation to determine whether the operation can be performed successfully.

RMAN chooses which backups to restore based on the criteria that you specify. For example, you can limit the restore to backups before a given point of time (within the current incarnation) with the untilClause.

When you run RESTORE in CATALOG mode with a backup control file, RMAN automatically adjusts the control file to reflect the structure of the restored database.

Locations of Restored Files

If you restore to the default location (that is, you do not run SET NEWNAME), then RMAN overwrites files with the same filenames. If you restore to a new location, then issue SET NEWNAME commands to rename the files and issue a SWITCH command to make the restored files current. If you do not issue SWITCH commands, then RMAN considers the restored files as valid copies for use in future restore operations.

If you do not run SET NEWNAME and RMAN detects that the default filename cannot be used (for example, because the filename is in use by another database that shares the storage), and if the file is an Oracle Managed File or is on an Automatic Storage Management disk group, then RMAN attempts to create a new file in the same location or disk group.

Note:

By default, RMAN does not restore a datafile if the file is in the correct place and its header contains the expected data (RMAN does not scan the datafile body for corrupt blocks). The FORCE option overrides this behavior and restores the requested files unconditionally.

Channel Allocation in a Restore

If you do not manually allocate channels, then RMAN allocates all automatic channels possibly needed by the RESTORE command, subject to any restrictions imposed by the use of the DEVICE TYPE option.

For example, assume you configure 3 separate sbt channels (each with different PARMS) and then configure parallelism for DISK and sbt as follows:

CONFIGURE DEVICE TYPE DISK PARALLELISM 2;
CONFIGURE DEVICE TYPE sbt PARALLELISM 3;
CONFIGURE DEFAULT DEVICE TYPE TO sbt;

If you run RESTORE in this configuration, then RMAN allocates three sbt channels and the two preconfigured DISK channels.

Restore Failover

If a backup piece, image copy or proxy copy is inaccessible (for instance, deleted from the device) or if a block is corrupted, then the RESTORE command automatically looks for a another usable copy of this backup piece or image copy on both the same device and other devices. If no usable copies are available, then RMAN searches for prior backups. RMAN continously searches for prior usable backups until it has exhaused all possibilities.

Restore failover also occurs when restoring archivelogs for use in RECOVER, BLOCKRECOVER and FLASHBACK operations. RMAN records messages about failover due to block corruption in the alert log and trace files.

See Oracle Database Backup and Recovery Advanced User's Guide for details on restore failover.

Restoring Files in a Real Application Cluster Configuration

In a Real Application Clusters configuration, RMAN automatically restores backups, control file copies, and datafile copies from channels that can read the files on tape or a local file system. For example, if channel 1 connected to instance 1 can read log 1000 from its tape drive, but channel 2 connected to instance 2 cannot read the same log from its tape drive, then channel 1 restores the log. Autolocation is automatically enabled when the channels meet any of the following criteria:

Different PARMS settings
Different CONNECT strings

See Also:
Oracle Database Backup and Recovery Basics to learn how to restore files

Restrictions and Usage Notes

To restore datafiles to their current location, the database must be started, mounted, or open with the tablespaces or datafiles to be restored offline. If the database is started but not mounted, then it is recommended that you only restore the control file, if necessary (refer to "Restrictions and Usage Notes for RESTORE CONTROLFILE"). To restore other files, mount the database and then continue.

Note:
When performing a database validation by using RESTORE ... VALIDATE, the database can be open.
To restore to a new location, run SET NEWNAME commands to rename the datafiles and SWITCH commands to make them the current database files. If you do not use SWITCH, then the repository lists restored datafiles as datafile copies.
If you use the FROM DATAFILECOPY option, then the allocated channels must be of DEVICE TYPE DISK.
If you use the FROM BACKUPSET operand, then the appropriate type of storage devices must be allocated for the backup sets that need to be restored. If the appropriate device is not allocated, then you may not be able to find a candidate backup set or copy to restore, and the RESTORE command fails.
RMAN only restores backups that were created on the same type of channels that are allocated for the RESTORE command.

For example, if you made some backups of a datafile to DISK channels and others to sbt channels, and only a DISK channel is allocated for the RESTORE command, RMAN will not restore backups that were created on sbt channels.
If there are no backups available for a lost datafile, RMAN will create an empty datafile with the checkpoint change as creation SCN. During recovery, all archived logs back to the creation of the datafile will be restored, and all changes during the history of the datafile will be re-applied to recreate its contents.
If datafile names are symbolic links, that is, files pointing to other files, then the control file stores the filenames of the link files but RMAN performs I/O on the datafiles pointed to by the link files. If a link file is lost and you RESTORE a datafile without re-creating the symbolic link, then RMAN restores the datafile to the location of the link file rather than to the location pointed to by the link.
If the database is started but not mounted in NOCATALOG mode, then the RESTORE SPFILE command requires the FROM AUTOBACKUP clause.
If you are restoring the server parameter file and the control file in a disaster recovery situation, you cannot run RESTORE CONTROLFILE FROM AUTOBACKUP, mount this control file, and then run RESTORE SPFILE without the FROM AUTOBACKUP clause.
Do not specify a datafile more than once in a restore job. For example, the following command is illegal because datafile 1 is both specified explicitly and implied by the SYSTEM tablespace:
```
RESTORE TABLESPACE SYSTEM DATAFILE 1;
```
You must have already configured a device type by using CONFIGURE (except for DISK, which is preconfigured) before specifying the DEVICE TYPE option.
You cannot manually allocate channels and then run RECOVER DEVICE TYPE.
RMAN cannot backup or restore locally-managed temporary tablespaces. RMAN can, however, back up and restore dictionary-managed temporary tablespaces.
RMAN does not support backup and recovery of the change tracking file. Note that database restore and recovery has no user-visible effect on change tracking. The next incremental backup after any recovery is able to use the change-tracking file.
If no suitable backups are available in the current incarnation of the database, then you can force RMAN to use backups from a previous incarnation. Using the CHANGE... UNAVAILABLE command, you can make all backups since the RESETLOGS that ended the incarnation unavailable. Run LIST RECOVERABLE to see valid parent incarnations.

Restrictions and Usage Notes for RESTORE CONTROLFILE

After you restore a backup control file, you must run RECOVER DATABASE and then open the database with the RESETLOGS option.
After restoring a backup control file, entries for tempfiles in locally-managed temporary tablespaces are removed. Hence, you must add new tempfiles to these tablespaces after you OPEN RESETLOGS. If you do not, then the database can display the following error for when attempting to sort: ORA-25153: Temporary Tablespace is Empty.

Table 2-27 indicates the restrictions that apply in different situations involving the RESTORE CONTROLFILE command.

Table 2-27 RESTORE CONTROLFILE Scenarios

	RESTORE CONTROLFILE;	RESTORE CONTROLFILE FROM AUTOBACKUP;	*RESTORE CONTROLFILE ... TO 'filename';*	*RESTORE CONTROLFILE ... FROM 'media_handle' or TAG 'user_tag';*
No catalog, target started in NOMOUNT state	Error. Must specify `FROM` `AUTOBACKUP`.	First run `SET` `DBID`. Restores to `CONTROL_FILES` locations.	First run `SET` `DBID`. Must specify `FROM` `AUTOBACKUP`. Restores only to `filename`.	First run `SET` `DBID`. Restores from specified file (cannot restore from `TAG`). If `TO` '`filename`' not used, restores to all `CONTROL_FILES` locations.
No catalog, target mounted or open	Error. Must use `TO` '`filename`', where `filename` is not in `CONTROL_FILES` list.	Error. Must use `TO` '`filename`', where `filename` is not in `CONTROL_FILES` list.	Restores only to `filename`, where `filename` is not in `CONTROL_FILES` list.	Restores from specified file. If `TO` '`filename`' not used, restores to all `CONTROL_FILES` locations.
Catalog, target started in NOMOUNT state	Restores to `CONTROL_FILES` locations. Run `SET` `DBID` only if `DB_NAME` not unique in catalog.	Only use with catalog for testing purposes.	Restores only to `filename`, where `filename` is not in `CONTROL_FILES` list.	Restores from specified file. If `TO` '`filename`' not used, restores to all `CONTROL_FILES` locations.
Catalog, target mounted or open	Error. Must use `TO` '`filename`', where `filename` is not in `CONTROL_FILES` list.	Do not use with catalog.	Restores only to `filename`, where `filename` is not in `CONTROL_FILES` list.	Restores from specified file. If `TO` '`filename`' not used, restores to all `CONTROL_FILES` locations.

Keywords and Parameters

restore

Syntax Element	Description
`CHANNEL` `'channel_id'`	Refer to the `restoreSpecOperand` clause.
`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. If the total number of physical and logical corruptions detected in a file is less than its `MAXCORRUPT` setting, the RMAN command completes and the database populates the `V$DATABASE_BLOCK_CORRUPTION` view with corrupt block ranges. If `MAXCORRUPT` is exceeded, the command terminates without populating the views. If the initialization parameter `DB_BLOCK_CHECKSUM=TRUE`, and if `MAXCORRUPT` and `NOCHECKSUM` are not set, then specifying `CHECK` `LOGICAL` detects all types of corruption that are possible to detect. Note: The `MAXCORRUPT` setting represents the total number of physical and logical corruptions permitted on a file.
`CHECK` `READONLY`	Checks the read-only datafiles to make sure they exist, are readable, and have the appropriate checkpoint. If any of these conditions is not met, then RMAN restores the files--whether or not they are read-only. By default, RMAN does not restore read-only files when you issue the `RESTORE` `DATABASE` command.
`DEVICE` `TYPE` deviceSpecifier	Allocates automatic channels for the specified device type only. For example, if you configure automatic disk and tape channels, and issue `RESTORE` `...` `DEVICE` `TYPE` `DISK`, then RMAN allocates only disk channels. See Also: "deviceSpecifier"
`FORCE`	Overrides the restartable restore feature and restores all files regardless of whether they need to be restored. If you do not specify `FORCE`, then RMAN restores a file only if its header information does not match the information in the control file.
`FROM` `{BACKUPSET` `\|` `DATAFILECOPY}`	Specifies whether RMAN should restore from a `DATAFILECOPY` on disk or a `BACKUPSET`. By default `RESTORE` chooses the most recent backup set or file copy, that is, the file copy or backup set that needs the least media recovery.
`FROM` `TAG` `=` `'tag_name'`	Refer to the `restoreSpecOperand` clause.
`PREVIEW [SUMMARY]`	When `PREVIEW` or `PREVIEW` `SUMMARY` is appended to any `RESTORE` command, instead of performing the restore RMAN will report the backups (on disk or sequential media) it will use during the restore. The output will be in the same format as is generated by the `LIST` `BACKUPS` and `LIST` `BACKUPS`... `SUMMARY` commands. See Also: "LIST", and specifically the `BACKUPS` and `SUMMARY` options.
untilClause	Limits the selection to backup sets or file copies that are suitable for a point-in-time recovery to the specified time. In the absence of any other criteria, RMAN selects the most current file copy or backup set to restore. Note that the time specified in the untilClause must fall within the current incarnation. See Also: "untilClause"
`VALIDATE`	Lets RMAN decide which backup sets, datafile copies, and archived logs need to be restored and then scans them to verify their contents. No files will be restored. Use this option periodically to verify that the copies and backup sets required to restore the specified files are intact and usable.

restoreObject

Syntax Element	Description
`restoreObject`	Specifies the objects to be restored. The `RESTORE` command restores full backups, incremental backups (level 0 only), or copies of datafiles, control files, and archived redo logs.
`archivelogRecordSpecifier`	Restores the specified range of archived redo logs. The default restore location is `DB_RECOVERY_FILE_DEST` (if one of `LOG_ARCHIVE_DEST_n` is configured to `USE_DB_RECOVERY_FILE_DEST` either implicitly or explicitly). Otherwise, the default restore filenames are constructed with the `LOG_ARCHIVE_FORMAT` and `LOG_ARCHIVE_DEST_1` parameters of the target database. These parameters combine in a port-specific fashion to derive the name of the restored log. You can override the default location with the `SET` `ARCHIVELOG` `DESTINATION` command. Because the `RECOVER` command automatically restores archived logs as needed, you should seldom need to restore logs manually. Possible reasons for manually restoring archived logs are to speed up recovery or to stage the logs to multiple destinations. See Also: "archivelogRecordSpecifier" Note: The database can be started, mounted, or open for this operation.
`CONTROLFILE`	Restores the current control file for a primary database. See Also: Table 2-27 for restrictions and usage notes. Note: You must always run the `RECOVER` command after restoring a control file, and must also always open the database with the `RESETLOGS` option.
`DATABASE [ SKIP [ FOREVER ] TABLESPACE tablespace_name ]`	Restores all datafiles in the database except those that are offline or read-only. Unlike `BACKUP` `DATABASE`, `RESTORE` `DATABASE` does not automatically include the control file and the server parameter file--you must issue additional `RESTORE` `CONTROLFILE` and `RESTORE` `SPFILE` commands to restore these files. If you specify the `CHECK` `READONLY` option, then RMAN examines the headers of all read-only datafiles and restores any that need restoring. Use an optional `SKIP` `TABLESPACE` `'tablespace_name'` argument to avoid restoring specified tablespaces, which is useful when you want to avoid restoring tablespaces containing temporary data. If you specify `SKIP` `FOREVER` `TABLESPACE`, then RMAN specifies the `DROP` option of `ALTER` `DATABASE` `DATAFILE` `...` `OFFLINE` when taking the datafiles that belong to the tablespace offline before the restore. The `DROP` option indicates that RMAN does not intend to recover these files and intends to drop their tablespaces from the database after the database is opened again. In other words, `FOREVER` indicates that RMAN never intends to do anything with the skipped tablespaces again.
`DATAFILE` `datafileSpec`	Restores the datafiles specified by filename or absolute datafile number. See Also: "datafileSpec"
`SPFILE` `[TO [PFILE]` `'``filename``']`	Restores a primary or `STANDBY` server parameter file to the location from which it was backed up (default), or to a different location specified by the `TO` clause. RMAN cannot overwrite a server parameter file currently in use by the target database. Specify `UNTIL` or `TAG` options of `RESTORE` to restore older versions of the server parameter file. By default RMAN restores the most current server parameter file. If the server parameter file is lost, connect to the target (and catalog if used) and then run `SET` `DBID`. Run `STARTUP` `FORCE` `NOMOUNT` before running `RESTORE` `SPFILE` (with `FROM` `AUTOBACKUP` if in `NOCATALOG` mode). Then run `STARTUP` `FORCE` to restart the database with the restored server parameter file. See Also: "Restrictions and Usage Notes for the SET DBID Command"
`STANDBY CONTROLFILE [ TO '``filename``' ]`	Restores the current control file for a standby database. See Also: Table 2-27 for restrictions and usage notes. Note: You must always run the `RECOVER` command after restoring a control file, and must also always open the database with the `RESETLOGS` option.
`TABLESPACE` `'tablespace_name'`	Restores all datafiles in the specified tablespaces. The translates the tablespace name internally into a list of datafiles. If you rename a tablespace (for example, from `users` to `customers`), then so long as an additional tablespace with the old name (`users`) has not been created, you can use either the old name (`users`) or the new name (`customers`) for the tablespace. RMAN detects that the tablespace has changed its name and updates the recovery catalog on the next resynchronization.

restoreSpecOperand

Syntax Element	Description
`restoreSpecOperand`	Specifies options for the `restoreObject` clause. Note: These parameters override the parameters with the same name at the `RESTORE` command level.
`CHANNEL` `'channel_id'`	Specifies the case-sensitive name of a channel to use for this restore operation. If you do not specify a channel, then `RESTORE` uses any available channel allocated with the correct device type.
`FROM` `AUTOBACKUP [autoBackupOptionList]`	Restores a control file autobackup. You can only specify this option on the `RESTORE` `CONTROLFILE` and `RESTORE` `SPFILE` commands. When restoring either type of file in `NOCATALOG` mode, the `FROM` `AUTOBACKUP` clause is required. RMAN begins the search on the current day or on the day specified with the `SET` `UNTIL`. If no autobackup is found in the current or `SET` `UNTIL` day, RMAN checks the previous day starting with sequence 256 (or the sequence specified by `MAXSEQ`) until it reaches 0. The search continues up to `MAXDAYS` days (default of 7, maximum of 366) from the current or `SET` `UNTIL` day. If no autobackup is found within `MAXDAYS` days, then RMAN signals an error and the command stops. See Also: Table 2-27 for restrictions and usage notes.
`FROM` `'``media_handle``'`	Specifies the name of the control file copy or backup piece containing a control file. The `media_handle` can be any backup piece that contains a backup of a control file: the control file backup does not need to be an autobackup. See Also: Table 2-27 for restrictions and usage notes.
`FROM` `TAG` [`=]` `'tag_name'`	Overrides the default selection of the most recent backups or file copy available. The tag restricts the automatic selection to backup sets or file copies that were created with the specified tag. If multiple backup sets or file copies have a matching tag, then RMAN selects the most recent one. Note that tag names are not case sensitive. See Also: "BACKUP" for a description of how a tag can be applied to an individual copy of a duplexed backup set, and for a description of the default filename format for tags

autoBackupOptList

Syntax Element	Description
`autoBackupOptList`	Parameters that control the search for a control file autobackup.
`DB_NAME = 'database_name'`	Provides a DB_NAME to be used in searching for control file autobackups.
`MAXDAYS =` `integer`	Limits the search for a control file autobackup to within the specified number of days in the past.
`MAXSEQ =` `integer`	Specifies the highest sequence number for the control file autobackup search.
`(RECOVERY AREA\| DB_RECOVERY_FILE_DEST) =` `quoted_string`	Specifies path to flash recovery area to search for autobackups. `RECOVERY AREA` and `DB_RECOVERY_FILE_DEST` are synonyms.
`DB_NAME =` `database_name`	Provides the `DB_NAME` of the database in the specified flash recovery area that is the target of the restore operation.
`DB_UNIQUE_NAME =` `{``identifier` `\|``quoted-string` `}`	Provides the `DB_UNIQUE_NAME` of the database in the specified flash recovery area that is the target of the restore operation.

Examples

Restoring a Tablespace: Example

This example takes a tablespace offline, restores it, then performs media recovery:

SQL "ALTER TABLESPACE users OFFLINE IMMEDIATE"; 
RESTORE TABLESPACE users; 
RECOVER TABLESPACE users;  
SQL "ALTER TABLESPACE users ONLINE";

Restoring the Control File When Using a Recovery Catalog: Example

This example restores the control file to its default location, replicates it automatically to all CONTROL_FILES locations, and mounts the database:

RUN
{ # SET DBID is not necessary when connected to a recovery catalog
  STARTUP FORCE NOMOUNT;
  RESTORE CONTROLFILE;
  ALTER DATABASE MOUNT;
}

Restoring the Control File with a Tag: Example

This NOCATALOG example restores the control file specified by a tag, and then mounts the database:

CONNECT TARGET /
STARTUP NOMOUNT;
SET DBID 320066378;  # required when restoring control file in NOCATALOG mode
RESTORE CONTROLFILE FROM TAG 'monday_cf_backup';
ALTER DATABASE MOUNT;

Restoring the Database with a Backup Control File: Example

This example restores the control file to a temporary location, replicates it to all control file locations specified in the CONTROL_FILES initialization parameter, and then restores and recovers the database:

CONNECT TARGET /
STARTUP NOMOUNT;
SET DBID 320066378;  # required when restoring control file in NOCATALOG mode
RUN
{
  ALLOCATE CHANNEL c1 DEVICE TYPE sbt;
  RESTORE CONTROLFILE TO '/tmp/control01.ctl' FROM AUTOBACKUP;
  RESTORE CONTROLFILE FROM '/tmp/control01.ctl'; # restores to all CONTROL_FILES locations
  ALTER DATABASE MOUNT;
  RESTORE DATABASE;
  RECOVER DATABASE;
}
ALTER DATABASE OPEN RESETLOGS;
# if the database uses locally-managed temporary tablespaces, then add new tempfiles
# to these tablespaces after the RESETLOGS
SQL "ALTER TABLESPACE temp ADD TEMPFILE ''?/oradata/trgt/temp01.dbf'' REUSE";

Restoring Archived Redo Logs to a New Location: Example

This example restores all archived redo logs to the /oracle/temp_restore directory:

RMAN> RUN
{ 
  SET ARCHIVELOG DESTINATION TO '/oracle/temp_restore';
  RESTORE ARCHIVELOG ALL;
}

Restoring a Control File Autobackup to a Nondefault Location: Example

This example restores the latest control file autobackup made on or before June 23, 2000 with a nondefault format of PROD_CF_AUTOBACKUP_%F. It starts searching for backups with a sequence number of 20, and searches backward for 5 months:

RMAN> SET DBID 320066378;  # required when restoring control file in NOCATALOG mode
RMAN> RUN
{
  SET UNTIL TIME '23-JUN-2001 00:00:00';
  SET CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE sbt TO 'prod_cf_autobackup_%F';
  ALLOCATE CHANNEL CHANNEL_1 DEVICE TYPE sbt;
  RESTORE CONTROLFILE TO '/tmp/autobackup_20001002.dbf' FROM AUTOBACKUP 
    MAXSEQ 20 MAXDAYS 150;
}

Restoring the Server Parameter File to Current Location: Example

The following series of commands restores the current server parameter file in NOCATALOG mode:

rman TARGET /
RMAN> SET DBID 1447326980 # set dbid to dbid of target database
RMAN> STARTUP FORCE NOMOUNT; # start instance with dummy SPFILE
RMAN> RUN
{
  ALLOCATE CHANNEL c1 DEVICE TYPE sbt;
  RESTORE SPFILE FROM AUTOBACKUP; # FROM AUTOBACKUP needed in NOCATALOG mode
}
RMAN> STARTUP FORCE; # start with restored SPFILE and open database

Previewing a Restore with RESTORE PREVIEW: Example

'The following example shows the results of a RESTORE PREVIEW, which identifies the backupsets to use in restoring datafile 1 of a database:

RMAN> restore datafile 1 preview;

Starting restore at 10-OCT-03
using target database controlfile instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=18 devtype=DISK


List of Backup Sets
===================

BS Key  Type LV Size       Device Type Elapsed Time Completion Time
------- ---- -- ---------- ----------- ------------ ---------------
25      Full    264M       DISK        00:00:42     10-OCT-03 
        BP Key: 25 Status: AVAILABLE Compressed: NO Tag: FOURTH_INC
        Piece Name: /ade/banand_hosted5/oracle/work/v1/0pf3hr3o_1
   List of Datafiles in backup set 25
   File LV Type Ckp SCN    Ckp Time  Name
   ---- -- ---- ---------- --------- ----
   1       Full 228006     10-OCT-03 /disk1/oracle/dbs/tbs_01.f
Finished restore at 10-OCT-03

Validating a Restore with RESTORE VALIDATE: Example

The following example illustrates using RESTORE VALIDATE for the restore of datafile 1, as in the previous example:

RMAN> RESTORE DATAFILE 1 VALIDATE;

Starting restore at 10-OCT-03
using channel ORA_DISK_1

channel ORA_DISK_1: starting validation of datafile backupset
channel ORA_DISK_1: restored backup piece 1
piece handle=/disk1/oracle/work/v1/0pf3hr3o_1 tag=FOURTH_INC
channel ORA_DISK_1: validation complete
Finished restore at 10-OCT-03