I am noticing a strange behavior with backups. The scenario goes like this:
1. I create a new database, call it test_db.
2. I set the recovery model to full.
3. If I try to create a transaction log backup, it obviously fails because a transaction log backup requires a valid full backup to be on hand.
4. I create a full backup
5. I can now create a transaction log backup
6. I use exec sp_delete_database_backuphistory @database_name = 'test_db'. This completes with no errors, and querying the msdb database confirms that the backup history has been removed for test_db.
7. At this point, I can still create a transaction log backup. Without a full backup available, this should fail, but does not. Does anyone know why this would be?