After recently upgrading a SQL Server instance to SQL Server 2012 a few days ago, you noticed that your application is not functioning properly. You decided to roll back the upgrade by downgrading the SQL Server database engine to SQL Server 2008 R2. After the downgrade of the database engine, you are unable to attach the databases or restore the backups of the databases, even though the database compatibility level is set to the downgraded version of SQL Server. You receive the following error message, when you attempt to restore the database:
This error message is generated because SQL Server automatically upgrades the database, when you restore or attach the database from lower version to higher version. SQL Server does not allow you to restore or attach a database from a higher version of SQL Server to a lower version of SQL Server.
Checkout my tip (ie. How to restore a SQL Server database to a lower version) in which I discussed one time procedure which we can follow to downgrade the database from a higher version (SQL Server 2012) of SQL Server to a lower version (SQL Server 2008 R2) of SQL Server.
This article is published on MSSQLTips.com.