What’s the story about log shipping?

Log shipping has a long history in SQL Server for high availability. Although officially log shipping was introduced in SQL Server 2000, it can be used to create jobs to do the same thing in 6.5 & 7.0 with creating customized jobs/SP (http://www.sqlservercentral.com/Forums/Topic603471-146-1.aspx).

Database Mirroring was introduced in SQL Server 2005 as a favorable solution over log shipping to high availability (https://www.simple-talk.com/blogs/2009/06/25/the-fall-and-rise-of-log-shipping/). 

There was one time that Microsoft announced to deprecate log shipping in the near feature. In the book “Microsoft SQL Server 2008R2 Unleashed” By Ray Rankins, Paul T. Bertucci etc. Chapter 18:

Nevertheless, it did not happen. In SQL Server 2012, Microsoft recommends retiring database mirroring by using AlwaysOn. If the editions do not support AlwaysOn, use Log Shipping: 

If your edition of SQL Server does not support AlwaysOn Availability Groups, use log shipping (http://technet.microsoft.com/en-us/library/ms143729.aspx)   

Also the updated version of the book “Microsoft SQL Server 2012 Unleashed” (by Ray Rankins, Paul T. Bertucci etc., page 1482) states:

Partial Database Backup, Partial Database Restore, and Piecemeal Database Restore

1.  Partial Backups – for very large databases that contain one or more read-only filegroups, but you want to exclude read-only filegroups


Partial backups are new in SQL Server 2005 (No partial backup in SQL Server 2000, but partial restore existed in SQL Server 2000). Although all SQL Server recovery models support partial backups, partial backups are designed for use under the simple recovery model to improve flexibility for backing up very large databases that contain one or more read-only filegroups.


Partial backups are useful whenever you want to exclude read-only filegroups. A partial backup resembles a full database backup, but a partial backup does not contain all the filegroups. Instead, for a read-write database, a partial backup contains the data in the primary filegroup, every read-write filegroup, and, optionally, one or more read-only files. A partial backup of a read-only database contains only the primary filegroup.


In short, Partial backups cover read/-write filegroups and, possibly, one or more read-only files or filegroups. Optionally, each partial backup can serve as the base of a series of one or more differential partial backups.


--Creating a Partial Backup


BACKUP DATABASE { database_name | @database_name_var }

 READ_WRITE_FILEGROUPS [ , <read_only_filegroup> [ ,...n ] ]

  TO <backup_device> [ ,...n ]

  [ <MIRROR TO clause> ] [ next-mirror-to ]

  [ WITH { DIFFERENTIAL | <general_WITH_options> [ ,...n ] } ]



2.  Partial Restore - for restoring a subset of database

Partial restore operations work with database filegroups. The primary filegroup is always restored, along with the files that you specify and their corresponding filegroups. The result is a subset of the database. Filegroups that are not restored are marked as offline and are not accessible.


Partial restore operations are accomplished with the PARTIAL clause of the RESTORE statement. You can also use the PARTIAL option when restoring a full database backup. Partial database restore of file backups is not supported.


A partial restore operation is particularly useful when you are:

·              Creating a subset of a database on another server for development or reporting purposes.

·              Restoring archived data.


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



   FILEGROUP = 'sales'

   FROM DISK='g:\mywind.dmp'


   MOVE 'mywind' TO 'g:\mw2.pri',

   MOVE 'mywind_log' TO 'g:\mw2.log',

   MOVE 'mywind_data_2' TO 'g:\mw2.dat2'

http://technet.microsoft.com/en-us/library/aa196613(v=sql.80).aspx for more.


3.  Piecemeal Restores – Enhanced version of Partial Database Restore: for databases containing multiple filegroups, bring it online through a piecemeal restore process starting with the primary filegroup

Piecemeal restore, which is new in SQL Server 2005, enhances Microsoft SQL Server 2000 partial restore (How enhanced? Does partial restore still work independently in SQL Server 2005?). 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.


============= See https://technet.microsoft.com/en-US/library/ms177425(v=SQL.110).aspx ========

This topic is relevant only for databases in SQL Server 2005 Enterprise Edition and later versions that contain multiple files or filegroups; and, under the simple mode, only for read-only filegroups.


In SQL Server 2005 and later versions, databases that contain multiple filegroups can be restored and recovered in stages through a process known as piecemeal restore. Piecemeal restore involves a series of restore sequences, starting with the primary filegroup and, in some cases, and one or more secondary filegroups. After the restore sequence is completed, recovered files, if they are valid and consistent with the database, can be brought online directly.

Piecemeal restore works with all recovery models, but is more flexible for the full and bulk-logged models than for the simple model.