If you back up a database, transaction log, or filegroup that contains errors, these errors will still exist when the backup is restored. In some cases, this can prevent a successful restore. Backup Exec enables you to check the logical and physical consistency of the data before and after a backup. SQL reports any consistency check failures in the Backup Exec job log. Symantec strongly recommends that you always run a consistency check either before or after the backup.
CHECKDB, CHECKCATALOG, and PHYSICAL_ONLY are performed for database-related operations.
CHECKFILEGROUP is performed for filegroup-related operations.
For more information concerning these utilities, see your MS SQL documentation.
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