Is it normal for backup size to increase even when database size remained the same? (4332267)

Chat now with support

Return

Feedback Submitted

Did this article solve an issue for you?

Select Rating

Title

Is it normal for backup size to increase even when database size remained the same?
Description

There was an increase in the backup size (less than 0.2 MB) after a second backup was taken 8 hours later (see attached). Note that the database size remained the same and there is no data change (ie. insert/update/delete). Shouldn't the backup size be exactly the same?
Resolution

Compression is data dependent. Any change (not necessary in size) in data can have changes in compression.
Just running a backup makes changes to the database. This is nothing to be concerned about. Plus there is no guarantee SQL Server is going to provide the data for a backup in the same exact order each time a backup is run. Just changing the order of extents received over VDI can have minor changes in compression.

If it is still a concern, perform two native disk backups of the same database and notice they will not compare equal. Zip them up and they will almost certainly differ in size.
Attachments

SOL76233_ls01_0

Feedback Submitted

Did this article solve an issue for you?

Select Rating

Title