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RESTORE (Transact-SQL)

Restores backups taken using the BACKUP command. This command enables you to perform the following restore scenarios:

  • Restore an entire database from a full database backup (a complete restore).

  • Restore part of a database (a partial restore).

  • Restore specific files or filegroups to a database (a file restore).

  • Restore specific pages to a database (a page restore).

  • Restore a transaction log onto a database (a transaction log restore).

  • Revert a database to the point in time captured by a database snapshot.

For more information about SQL Server restore scenarios, see Restore and Recovery Overview (SQL Server) and Implementing Restore Scenarios for SQL Server Databases.

NoteNote

For more information about descriptions of the arguments, see RESTORE Arguments (Transact-SQL).

Topic link icon Transact-SQL Syntax Conventions


--To Restore an Entire Database from a Full database backup (a Complete Restore):
RESTORE DATABASE { database_name | @database_name_var } 
 [ FROM <backup_device> [ ,...n ] ]
 [ WITH 
   {
    [ RECOVERY | NORECOVERY | STANDBY = 
        {standby_file_name | @standby_file_name_var } 
       ]
   | ,  <general_WITH_options> [ ,...n ]
   | , <replication_WITH_option>
   | , <change_data_capture_WITH_option>
   | , <service_broker_WITH options> 
   | , <point_in_time_WITH_options—RESTORE_DATABASE> 
   } [ ,...n ]
 ]
[;]

--To perform the first step of the initial restore sequence
-- of a piecemeal restore:
RESTORE DATABASE { database_name | @database_name_var } 
   <files_or_filegroups> [ ,...n ]
 [ FROM <backup_device> [ ,...n ] ] 
   WITH 
      PARTIAL, NORECOVERY 
      [  , <general_WITH_options> [ ,...n ] 
       | , <point_in_time_WITH_options—RESTORE_DATABASE> 
      ] [ ,...n ] 
[;]

--To Restore Specific Files or Filegroups: 
RESTORE DATABASE { database_name | @database_name_var } 
   <file_or_filegroup> [ ,...n ]
 [ FROM <backup_device> [ ,...n ] ] 
   WITH 
   {
      [ RECOVERY | NORECOVERY ]
      [ , <general_WITH_options> [ ,...n ] ]
   } [ ,...n ] 
[;]

--To Restore Specific Pages: 
RESTORE DATABASE { database_name | @database_name_var } 
   PAGE = 'file:page [ ,...n ]' 
 [ , <file_or_filegroups> ] [ ,...n ]
 [ FROM <backup_device> [ ,...n ] ] 
   WITH 
       NORECOVERY   
      [ , <general_WITH_options> [ ,...n ] ]
[;]

--To Restore a Transaction Log:
RESTORE LOG { database_name | @database_name_var } 
 [ <file_or_filegroup_or_pages> [ ,...n ] ]
 [ FROM <backup_device> [ ,...n ] ] 
 [ WITH 
   {
     [ RECOVERY | NORECOVERY | STANDBY = 
        {standby_file_name | @standby_file_name_var } 
       ]
    | ,  <general_WITH_options> [ ,...n ]
    | , <replication_WITH_option>
    | , <point_in_time_WITH_options—RESTORE_LOG> 
   } [ ,...n ]
 ] 
[;]

--To Revert a Database to a Database Snapshot:   
RESTORE DATABASE { database_name | @database_name_var } 
FROM DATABASE_SNAPSHOT = database_snapshot_name 

<backup_device>::=
{ 
   { logical_backup_device_name |
      @logical_backup_device_name_var }
 | { DISK | TAPE } = { 'physical_backup_device_name' |
      @physical_backup_device_name_var } 
} 

<files_or_filegroups>::= 
{ 
   FILE = { logical_file_name_in_backup | @logical_file_name_in_backup_var } 
 | FILEGROUP = { logical_filegroup_name | @logical_filegroup_name_var } 
 | READ_WRITE_FILEGROUPS
} 

<general_WITH_options> [ ,...n ]::= 
--Restore Operation Options
   MOVE 'logical_file_name_in_backup' TO 'operating_system_file_name' 
          [ ,...n ] 
 | REPLACE 
 | RESTART 
 | RESTRICTED_USER 

--Backup Set Options
 | FILE = { backup_set_file_number | @backup_set_file_number } 
 | PASSWORD = { password | @password_variable } 

--Media Set Options
 | MEDIANAME = { media_name | @media_name_variable } 
 | MEDIAPASSWORD = { mediapassword | @mediapassword_variable } 
 | BLOCKSIZE = { blocksize | @blocksize_variable } 

--Data Transfer Options
 | BUFFERCOUNT = { buffercount | @buffercount_variable } 
 | MAXTRANSFERSIZE = { maxtransfersize | @maxtransfersize_variable }

--Error Management Options
 | { CHECKSUM | NO_CHECKSUM } 
 | { STOP_ON_ERROR | CONTINUE_AFTER_ERROR } 

--Monitoring Options
 | STATS [ = percentage ] 

--Tape Options
 | { REWIND | NOREWIND } 
 | { UNLOAD | NOUNLOAD } 

<replication_WITH_option>::=
 | KEEP_REPLICATION 

<change_data_capture_WITH_option>::=
 | KEEP_CDC

<service_broker_WITH_options>::= 
 | ENABLE_BROKER 
 | ERROR_BROKER_CONVERSATIONS 
 | NEW_BROKER 


<point_in_time_WITH_options—RESTORE_DATABASE>::= 
 | {
   STOPAT = { 'datetime'| @datetime_var } 
 | STOPATMARK = { 'lsn:lsn_number' }
                 [ AFTER 'datetime'] 
 | STOPBEFOREMARK = {  'lsn:lsn_number' }
                 [ AFTER 'datetime'] 
   } 

<point_in_time_WITH_options—RESTORE_LOG>::= 
 | {
   STOPAT = { 'datetime'| @datetime_var } 
 | STOPATMARK = { 'mark_name' | 'lsn:lsn_number' }
                 [ AFTER 'datetime'] 
 | STOPBEFOREMARK = { 'mark_name' | 'lsn:lsn_number' }
                 [ AFTER 'datetime'] 
   } 

For descriptions of the arguments, see RESTORE Arguments (Transact-SQL).

During an offline restore, if the specified database is in use, RESTORE forces the users off after a short delay. For online restore of a non-primary filegroup, the database can stay in use except when the filegroup being restored is being taken offline. Any data in the specified database is replaced by the restored data.

For more information about database recovery, see Understanding How Restore and Recovery of Backups Work in SQL Server and Implementing Restore Scenarios for SQL Server Databases.

Cross-platform restore operations, even between different processor types, can be performed as long as the collation of the database is supported by the operating system.

RESTORE can be restarted after an error. In addition, you can instruct RESTORE to continue despite errors, and it restores as much data as possible (see the CONTINUE_AFTER_ERROR option). For more information, see Responding to SQL Server Restore Errors Caused by Damaged Backups.

RESTORE is not allowed in an explicit or implicit transaction.

Restoring a damaged master database is performed using a special procedure. For more information, see Considerations for Restoring the master Database.

Backups created with Microsoft SQL Server cannot be restored to an earlier version of SQL Server.

Restoring a database clears the plan cache for the instance of SQL Server. Clearing the plan cache causes a recompilation of all subsequent execution plans and can cause a sudden, temporary decrease in query performance. As of SQL Server 2005 Service Pack 2, for each cleared cachestore in the plan cache, the SQL Server error log contains the following informational message: "SQL Server has encountered %d occurrence(s) of cachestore flush for the '%s' cachestore (part of plan cache) due to some database maintenance or reconfigure operations". This message is logged every five minutes as long as the cache is flushed within that time interval.

The database being restored must be at least version 80 (SQL Server 2000) to restore to SQL Server 2008 R2. SQL Server 2000 or SQL Server 2005 databases that have a compatibility level less than 80 will be set to compatibility 80 when restored.

NoteNote

After you restore a SQL Server 2005 or SQL Server 2000 database to SQL Server 2008 R2, the database becomes available immediately and is then automatically upgraded. If the database has full-text indexes, the upgrade process either imports, resets, or rebuilds them, depending on the setting of the upgrade_option server property. If the upgrade option is set to import (upgrade_option = 2) or rebuild (upgrade_option = 0), the full-text indexes will be unavailable during the upgrade. Depending the amount of data being indexed, importing can take several hours, and rebuilding can take up to ten times longer. When the upgrade option is set to import, the associated full-text indexes are rebuilt if no full-text catalog is available. To change the setting of the upgrade_option server property, use sp_fulltext_service.

Restore Scenarios

SQL Server supports a variety of restore scenarios:

Discontinued RESTORE Keywords

The following keywords were discontinued in SQL Server 2008:

Discontinued keyword

Replaced by…

Example of replacement keyword

LOAD

RESTORE

RESTORE DATABASE

TRANSACTION

LOG

RESTORE LOG

DBO_ONLY

RESTRICTED_USER

RESTORE DATABASE ... WITH RESTRICTED_USER

Requirement for Restoring an Encrypted Database

To restore a database that is encrypted, you must have access to the certificate or asymmetric key that was used to encrypt the database. Without the certificate or asymmetric key, the database cannot be restored. As a result, the certificate that is used to encrypt the database encryption key must be retained as long as the backup is needed. For more information, see SQL Server Certificates and Asymmetric Keys.

Databases Enabled for vardecimal Storage Format

Backup and restore work correctly with the vardecimal storage format. For more information about vardecimal storage format, see Storing Decimal Data As Variable Length.

Comparison of RECOVERY and NORECOVERY

Roll back is controlled by the RESTORE statement through the [ RECOVERY | NORECOVERY ] options:

  • NORECOVERY specifies that roll back not occur. This allows roll forward to continue with the next statement in the sequence.

    In this case, the restore sequence can restore other backups and roll them forward.

  • RECOVERY (the default) indicates that roll back should be performed after roll forward is completed for the current backup.

    Recovering the database requires that the entire set of data being restored (the roll forward set) is consistent with the database. If the roll forward set has not been rolled forward far enough to be consistent with the database and RECOVERY is specified, the Database Engine issues an error.

Redoing a Restore

Undoing the effects of a restore is not possible; however, you can negate the effects of the data copy and roll forward by starting over on a per-file basis. To start over, restore the desired file and perform the roll forward again. For example, if you accidentally restored too many log backups and overshot your intended stopping point, you would have to restart the sequence.

A restore sequence can be aborted and restarted by restoring the entire contents of the affected files.

Restore Full-Text Data

Full-text data is restored together with other database data during a complete restore. Using the regular RESTORE DATABASE database_name FROM backup_device syntax, the full-text files are restored as part of the database file restore.

The RESTORE statement also can be used to perform restores to alternate locations, differential restores, file and filegroup restores, and differential file and filegroup restores of full-text data. In addition, RESTORE can restore full-text files only, as well as with database data.

NoteNote

Full-text catalogs imported from SQL Server 2005 or SQL Server 2000 are still treated as database files. For these, the SQL Server 2005 procedure for backing up full-text catalogs remains applicable, except that pausing and resuming during the backup operation are no longer necessary. For more information, see Backing Up and Restoring Full-Text Catalogs in SQL Server 2005 Books Online.

Database Settings and Restoring

During a restore, most of the database options that are settable using ALTER DATABASE are reset to the values in force at the time of the end of backup.

NoteNote

This behavior differs from versions of SQL Server before SQL Server 2000.

Using the WITH RESTRICTED_USER option, however, overrides this behavior for the user access option setting. This setting is always set following a RESTORE statement, which includes the WITH RESTRICTED_USER option.

Backup and Restore History Tables

SQL Server includes backup and restore history tables that track the backup and restore activity for each server instance. When a restore is performed, the backup history tables are also modified. For information on these tables, see Viewing Information About Backups.

RESTORE LOG

RESTORE LOG can include a file list to allow for creation of files during roll forward. This is used when the log backup contains log records written when a file was added to the database.

NoteNote

For a database using the full or bulk-logged recovery model, in most cases you must back up the tail of the log before restoring the database. Restoring a database without first backing up the tail of the log results in an error, unless the RESTORE DATABASE statement contains either the WITH REPLACE or the WITH STOPAT clause, which must specify a time or transaction that occurred after the end of the data backup. For more information about tail-log backups, see Tail-Log Backups.

Online Restore

NoteNote

Online restore is allowed only in SQL Server 2005 Enterprise Edition and later versions.

Where online restore is supported, if the database is online, file restores and page restores are automatically online restores and, also, restores of secondary filegroup after the initial stage of a piecemeal restore.

NoteNote

Online restores can involve deferred transactions.

For more information, see Performing Online Restores.

Piecemeal Restore

Piecemeal restore, which was new in SQL Server 2005, enhances Microsoft SQL Server 2000 partial restore. Piecemeal restore allows filegroups to be restored after an initial, partial restore of the primary and some of the secondary filegroups. Filegroups that are not restored are marked as offline and are not accessible. The offline filegroups, however, can be restored later by a file restore. To allow the entire database to be restored in stages at different times, piecemeal restore maintain checks to ensure that the database will be consistent in the end.

NoteNote

In SQL Server 2000, a partial restore can only be done from a full database backup. This restriction was removed in SQL Server 2005.

If a partial restore sequence excludes any FILESTREAM filegroup, point-in-time restore is not supported. You can force the restore sequence to continue. However, the FILESTREAM filegroups that are omitted from your RESTORE statement can never be restored. To force a point-in-time restore, specify the CONTINUE_AFTER_ERROR option together with the STOPAT, STOPATMARK, or STOPBEFOREMARK option, which you must also specify in your subsequent RESTORE LOG statements. If you specify CONTINUE_AFTER_ERROR, the partial restore sequence succeeds and the FILESTREAM filegroup becomes unrecoverable.

For more information about piecemeal restore, see Performing Piecemeal Restores.

Reverting a Database to a Database Snapshot

A revert database operation (specified using the DATABASE_SNAPSHOT option) takes a full source database back in time by reverting it to the time of a database snapshot, that is, overwriting the source database with data from the point in time maintained in the specified database snapshot. Only the snapshot to which you are reverting can currently exist. The revert operation then rebuilds the log (therefore, you cannot later roll forward a reverted database to the point of user error).

Data loss is confined to updates to the database since the snapshot's creation. The metadata of a reverted database is the same as the metadata at the time of snapshot creation. However, reverting to a snapshot drops all the full-text catalogs.

Reverting from a database snapshot is not intended for media recovery. Unlike a regular backup set, the database snapshot is an incomplete copy of the database files. If either the database or the database snapshot is corrupted, reverting from a snapshot is likely to be impossible. Furthermore, even when possible, reverting in the event of corruption is unlikely to correct the problem.

Restrictions on Reverting

Reverting is unsupported under the following conditions:

  • The source database contains any read-only or compressed filegroups.

  • Any files are offline that were online when the snapshot was created.

  • More than one snapshot of the database currently exists.

For more information, see Reverting to a Database Snapshot.

If the database being restored does not exist, the user must have CREATE DATABASE permissions to be able to execute RESTORE. If the database exists, RESTORE permissions default to members of the sysadmin and dbcreator fixed server roles and the owner (dbo) of the database (for the FROM DATABASE_SNAPSHOT option, the database always exists).

RESTORE permissions are given to roles in which membership information is always readily available to the server. Because fixed database role membership can be checked only when the database is accessible and undamaged, which is not always the case when RESTORE is executed, members of the db_owner fixed database role do not have RESTORE permissions.

A backup operation may optionally specify passwords for a media set, a backup set, or both. When a password has been defined on a media set or backup set, you must specify the correct password or passwords in the RESTORE statement. These passwords prevent unauthorized restore operations and unauthorized appends of backup sets to media using SQL Server tools. However, password-protected media can be overwritten by the BACKUP statement's FORMAT option.

Security noteSecurity Note

The protection provided by this password is weak. It is intended to prevent an incorrect restore using SQL Server tools by authorized or unauthorized users. It does not prevent the reading of the backup data by other means or the replacement of the password. This feature will be removed in a future version of Microsoft SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. The best practice for protecting backups is to store backup tapes in a secure location or back up to disk files that are protected by adequate access control lists (ACLs). The ACLs should be set on the directory root under which backups are created.

NoteNote

The AdventureWorks2008R2 database is shown for illustration. AdventureWorks2008R2 is one of the sample databases in SQL Server. Adventure Works Cycles is a fictional manufacturing company used to demonstrate database concepts and scenarios. For more information about this database, see AdventureWorks2008R2 Sample Databases.

All the examples assume that a full database backup has been performed.

The RESTORE examples include the following:

NoteNote

For additional examples, see Examples of Restore Sequences for Several Restore Scenarios and also the restore how-to topics that are listed in Backing Up and Restoring How-to Topics (Transact-SQL).

A. Restoring a full database

The following example restores a full database backup from the AdventureWorks2008R2Backups logical backup device. For an example of creating this device, see Backup Devices.

RESTORE DATABASE AdventureWorks2008R2 
   FROM AdventureWorks2008R2Backups
NoteNote

For a database using the full or bulk-logged recovery model, SQL Server requires in most cases that you back up the tail of the log before restoring the database. For more information, see Tail-Log Backups.

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B. Restoring full and differential database backups

The following example restores a full database backup followed by a differential backup from the Z:\SQLServerBackups\AdventureWorks2008R2.bak backup device, which contains both backups. The full database backup to be restored is the sixth backup set on the device (FILE = 6), and the differential database backup is the ninth backup set on the device (FILE = 9). As soon as the differential backup is recovered, the database is recovered.

RESTORE DATABASE AdventureWorks2008R2
   FROM DISK = 'Z:\SQLServerBackups\AdventureWorks2008R2.bak'
   WITH FILE = 6
      NORECOVERY;
RESTORE DATABASE AdventureWorks2008R2
   FROM DISK = 'Z:\SQLServerBackups\AdventureWorks2008R2.bak'
   WITH FILE = 9
      RECOVERY;

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C. Restoring a database using RESTART syntax

The following example uses the RESTART option to restart a RESTORE operation interrupted by a server power failure.

-- This database RESTORE halted prematurely due to power failure.
RESTORE DATABASE AdventureWorks2008R2
   FROM AdventureWorks2008R2Backups
-- Here is the RESTORE RESTART operation.
RESTORE DATABASE AdventureWorks2008R2 
   FROM AdventureWorks2008R2Backups WITH RESTART

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D. Restoring a database and move files

The following example restores a full database and transaction log and moves the restored database into the C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Data directory.

RESTORE DATABASE AdventureWorks2008R2
   FROM AdventureWorks2008R2Backups
   WITH NORECOVERY, 
      MOVE 'AdventureWorks2008R2_Data' TO 
'C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Data\NewAdvWorks2008R2.mdf', 
      MOVE 'AdventureWorks2008R2_Log' 
TO 'C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Data\NewAdvWorks2008R2.ldf'
RESTORE LOG AdventureWorks2008R2
   FROM AdventureWorks2008R2Backups
   WITH RECOVERY

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E. Copying a database using BACKUP and RESTORE

The following example uses both the BACKUP and RESTORE statements to make a copy of the AdventureWorks2008R2 database. The MOVE statement causes the data and log file to be restored to the specified locations. The RESTORE FILELISTONLY statement is used to determine the number and names of the files in the database being restored. The new copy of the database is named TestDB. For more information, see RESTORE FILELISTONLY (Transact-SQL).

BACKUP DATABASE AdventureWorks2008R2 
   TO AdventureWorks2008R2Backups ;

RESTORE FILELISTONLY 
   FROM AdventureWorks2008R2Backups ;

RESTORE DATABASE TestDB 
   FROM AdventureWorks2008R2Backups 
   WITH MOVE 'AdventureWorks2008R2_Data' TO 'C:\MySQLServer\testdb.mdf',
   MOVE 'AdventureWorks2008R2_Log' TO 'C:\MySQLServer\testdb.ldf';
GO

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F. Restoring to a point-in-time using STOPAT

The following example restores a database to its state as of 12:00 AM on April 15, 2020 and shows a restore operation that involves multiple log backups. On the backup device, AdventureWorks2008R2Backups, the full database backup to be restored is the third backup set on the device (FILE = 3), the first log backup is the fourth backup set (FILE = 4), and the second log backup is the fifth backup set (FILE = 5).

RESTORE DATABASE AdventureWorks2008R2
   FROM AdventureWorks2008R2Backups
   WITH FILE=3, NORECOVERY;

RESTORE LOG AdventureWorks2008R2
   FROM AdventureWorks2008R2Backups
   WITH FILE=4, NORECOVERY, STOPAT = 'Apr 15, 2020 12:00 AM';

RESTORE LOG AdventureWorks2008R2
   FROM AdventureWorks2008R2Backups
   WITH FILE=5, NORECOVERY, STOPAT = 'Apr 15, 2020 12:00 AM';
RESTORE DATABASE AdventureWorks2008R2 WITH RECOVERY; 

[Top of examples]

G. Restoring the transaction log to a mark

The following example restores the transaction log to the mark in the marked transaction named ListPriceUpdate.

USE AdventureWorks2008R2;
GO
BEGIN TRANSACTION ListPriceUpdate
   WITH MARK 'UPDATE Product list prices';
GO

UPDATE Production.Product
   SET ListPrice = ListPrice * 1.10
   WHERE ProductNumber LIKE 'BK-%';
GO

COMMIT TRANSACTION ListPriceUpdate;
GO

-- Time passes. Regular database 
-- and log backups are taken.
-- An error occurs in the database.
USE master
GO

RESTORE DATABASE AdventureWorks2008R2
FROM AdventureWorks2008R2Backups
WITH FILE = 3, NORECOVERY;
GO

RESTORE LOG AdventureWorks2008R2
   FROM AdventureWorks2008R2Backups 
   WITH FILE = 4,
   RECOVERY, 
   STOPATMARK = 'UPDATE Product list prices';

[Top of examples]

H. Restoring using TAPE syntax

The following example restores a full database backup from a TAPE backup device.

RESTORE DATABASE AdventureWorks2008R2 
   FROM TAPE = '\\.\tape0'

[Top of examples]

I. Restoring using FILE and FILEGROUP syntax

The following example restores a database named MyDatabase that has two files, one secondary filegroup, and one transaction log. The database uses the full recovery model.

The database backup is the ninth backup set in the media set on a logical backup device named MyDatabaseBackups. Next, three log backups, which are in the next three backup sets (10, 11, and 12) on the MyDatabaseBackups device, are restored by using WITH NORECOVERY. After restoring the last log backup, the database is recovered.

NoteNote

Recovery is performed as a separate step to reduce the possibility of you recovering too early, before all of the log backups have been restored.

In the RESTORE DATABASE, notice that there are two types of FILE options. The FILE options preceding the backup device name specify the logical file names of the database files that are to be restored from the backup set; for example, FILE = 'MyDatabase_data_1'. This backup set is not the first database backup in the media set; therefore, its position in the media set is indicated by using the FILE option in the WITH clause, FILE=9.

RESTORE DATABASE MyDatabase
   FILE = 'MyDatabase_data_1',
   FILE = 'MyDatabase_data_2',
   FILEGROUP = 'new_customers'
   FROM MyDatabaseBackups
   WITH 
      FILE = 9,
      NORECOVERY;
GO
-- Restore the log backups.
RESTORE LOG MyDatabase
   FROM MyDatabaseBackups
   WITH FILE = 10, 
      NORECOVERY;
GO
RESTORE LOG MyDatabase
   FROM MyDatabaseBackups
   WITH FILE = 11, 
      NORECOVERY;
GO
RESTORE LOG MyDatabase
   FROM MyDatabaseBackups
   WITH FILE = 12, 
      NORECOVERY;
GO
--Recover the database:
RESTORE DATABASE MyDatabase WITH RECOVERY;
GO

[Top of examples]

J. Reverting from a database snapshot

The following example reverts a database to a database snapshot. The example assumes that only one snapshot currently exists on the database. For an example of how to create this database snapshot, see How to: Create a Database Snapshot (Transact-SQL).

NoteNote

Reverting to a snapshot drops all the full-text catalogs.

USE master  
RESTORE DATABASE AdventureWorks2008R2 FROM DATABASE_SNAPSHOT = 'AdventureWorks2008R2_dbss1800';
GO

For more information, see Reverting to a Database Snapshot.

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