A copy-only backup is a SQL Server backup that is independent of the sequence of conventional SQL Server backups. Usually, taking a backup changes the database and affects how later backups are restored. However, occasionally, it is useful to take a backup for a special purpose without affecting the overall backup and restore procedures for the database. copy-only backups serve this purpose. The transaction log is never truncated after a copy-only backup.
The types of copy-only backups are as follows:
Copy-only full backups (all recovery models)
A copy-only full backup cannot serve as a differential base or differential backup and does not affect the differential base.
Copy-only log backups (full recovery model and bulk-logged recovery model only)
A copy-only log backup preserves the existing log archive point and, therefore, does not affect the sequencing of regular log backups. A copy-only log backup can sometimes be useful for performing an online restore.
The types of copy-only backups are as follows:
Copy-only full backups (all recovery models)
A copy-only full backup cannot serve as a differential base or differential backup and does not affect the differential base.
Copy-only log backups (full recovery model and bulk-logged recovery model only)
A copy-only log backup preserves the existing log archive point and, therefore, does not affect the sequencing of regular log backups. A copy-only log backup can sometimes be useful for performing an online restore.
