This post show you how to fix 'The transaction log for the database is null due to 'OLDEST_PAGE' in SQL Server.

Sometimes when you execute insert update or delete statement on a table in SQL Server you get the above error. To fix the problem you can change Recovery Model to Simple then Shrink Files Log.

- Right click on your database, then select Properties => Options => Recovery Model => Simple

- Right click on your database, then select Database Tasks => Shrink => Files => Log

Next, You can check your db log file size at Database Properties => Files => Database Files => Path

If you want to check full sql server log, you can open Log File Viewer at SSMS => Database => Management => SQL Server Logs => Current

And don't forget to check your disk make sure it not full