Copy-Only Backups (Simple Recovery Model)
Taking a backup normally changes the database, in turn affecting other backups and how they are restored. For example, a regular data backup can serve a differential base for one or more subsequent differential backups. Sometimes, however, a data backup must be taken for a special purpose and should not affect the overall backup and restore procedures for the database. For this purpose, SQL Server 2005 introduces copy-only backups, which are independent of the normal sequence of backups.
A copy-only backup does not impact the differential bitmap, so subsequent differential backups are unaffected by the copy-only backup. Therefore, a copy-only backup cannot serve as a differential base.
SQL Server Management Studio does not support copy-only backups. To create or restore a copy-only backup you must use the BACKUP and RESTORE Transact-SQL statements. To create a copy-only backup, use the COPY_ONLY option in a BACKUP DATABASE.
COPY_ONLY backups are recorded in the backupset table in the is_copy_only column. For more information, see backupset (Transact-SQL).
See Also
Concepts
Backup Under the Simple Recovery Model
Overview of the Recovery Models
Other Resources
BACKUP (Transact-SQL)
RESTORE (Transact-SQL)