The same First and the Last LSN I use SQL Express and my database has the following backup schedule:


Full backup - 24 hours
Differential backups - 6 hours
Transaction log backups - 30 minutes


My question is:

I have checked LSNs of transaction log backups that were made last night and discovered that one of them has the same First LSN and the Last LSN. 

Why?
Was it an error?
This isn't an error. It means that there weren't any changes in the database.