SQL Server Backup and Restore - Simple Talk

Chapter 3: Full Database Backups
These results represent a considerable saving, in both storage space and processing time,
over non-compressed backups.
If you're wondering whether or not the compression rates should be roughly consistent
across all your databases, then the short answer is no. Character data, such as that stored
in our DatabaseForFullBackups database compresses very well. However, some
databases may contain data that doesn't compress as readily such as FILESTREAM and
image data, and so space savings will be less.
Verifying Backups
Having discussed the basic concepts of backup verification in Chapter 2,
Listing 3-11 shows a simple script to perform a checksum during a backup of our
DatabaseForFullBackups database, followed by a RESTORE VERIFYONLY,
recalculating the checksum.
BACKUP DATABASE [DatabaseForFullBackups]
TO DISK = N'C:\SQLBackups\Chapter3\DatabaseForFullBackups_Full_Native_Checksum.bak'
WITH CHECKSUM
GO
RESTORE VERIFYONLY
FROM DISK = N'C:\SQLBackups\Chapter3\DatabaseForFullBackups_Full_Native_Checksum.bak'
WITH CHECKSUM
Listing 3-11: Backup verification examples.
Hopefully you'll get output to the effect that the backup is valid!
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