SQL Server 2008 Books Online (October 2009)
Recovering to a Log Sequence Number (LSN)

This topic is relevant only for databases that are using the full or bulk-logged recovery models.

SQL Server 2005 and later versions let you use a log sequence number (LSN) to define the recovery point for a restore operation. This is a specialized feature that is intended for tools vendors and is unlikely to be generally useful.

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For information about the requirements for restoring to a specific recovery point, see Restoring a Database to a Point Within a Backup.

Transact-SQL Syntax for Restoring to an LSN

By using a RESTORE statement, you can stop at or immediately before the LSN, as follows:

  • Use the WITH STOPATMARK = 'lsn:<lsn_number>' clause, where lsn:<lsnNumber> is a string that specifies that the log record that contains the specified LSN is the recovery point.
    STOPATMARK roll forwards to the LSN and includes that log record in the roll forward.
  • Use the WITH STOPBEFOREMARK = 'lsn:<lsn_number>' clause, where lsn:<lsnNumber> is a string that specifies that the log record immediately before the log record that contains the specified LSN number is the recovery point.
    STOPBEFOREMARK rolls forward to the LSN and excludes that log record from the roll forward.

Typically, a specific transaction is selected to be included or excluded. Although not required, in practice, the specified log record is a transaction-commit record.

For more information about how to use LSNs, see Log Sequence Numbers and Restore Planning.

For more information about point-in-time restores, see Restoring a Database to a Point Within a Backup.

Examples

The following example assumes that the AdventureWorks database has been changed to use the full recovery model.

RESTORE LOG AdventureWorks FROM DISK = 'c:\adventureworks_log.bak' 
WITH STOPATMARK = 'lsn:15000000040000037'
GO
See Also

Concepts

Applying Transaction Log Backups
Introduction to Log Sequence Numbers

Other Resources

RESTORE (Transact-SQL)
Implementing Restore Scenarios for SQL Server Databases
Restoring a Database to a Point Within a Backup
Working with Restore Sequences for SQL Server Databases

Help and Information

Getting SQL Server 2008 Assistance
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