I have a database on SQL 2008 R2 with compatibility level 80 and I want to change it to 90 or 100. I assumed that after changing, I may find a regression in our application's performance.
Many backups (like full, differential, and log) will be taken while using the new compatibility level 90 or 100. This database is also configured with log shipping.
My question is can I change compatibility level back to 80 safely without threats or must I take any considerations?