We are running six transaction log backups every day on our SQL Server with three hours gap for each succeeding pair. I have noticed the 'data size change' column of the transaction log backups on the server to show 630%, -21%, 0%, 2%, 3%, and -83%. I don't know what these values mean. Sometimes these go up to 1854%. Can anyone tell me what these values mean, and if we should be worried about them?
After looking around, it's hard to find good info on this, so what I'm giving you is a best guess based on what I can research. I would say that the data size change is the change in data since the last backup. You can see the larger percentages after a reindexing of the database (among other things), as all of those are captured as transactions in the log. Subsequent backups would show a reduction in the amount backup up as the transactions stabilized, hence the negative percentages. I don't think this is anything to be worried about. I'll give you some links on what I'm basing this off of.