Can't disable Vardecimal Storage Format

Question

I recently moved a database from a 'SQL Server 2005 SP1' instance to 'SQL Server 2008 SP1' (using detach - attach). I now need to move it back but it fails with the error:

The database 'MyDB' cannot be opened because it is version 655. This server supports version 612 and earlier. A downgrade path is not supported.

After a bit of research I believe this is related to the new database option 'Vardecimal Storage Format' which has somehow been set ON for all my databases. I did not set this on myself, but if I check the database options in Management Studio (2008) I can see it is set to 'True' for all my databases. Also, this particular option is disabled in the UI, so I cannot turn it off.

I then tried the following to turn it off:

exec sp_db_vardecimal_storage_format 'MyDB', 'OFF' go

which reported success, but when I check the options it is still ON.

I then read this very detailed article: "http://msdn.microsoft.com/en-us/library/bb508963.aspx" which states the following requirements to turn this option off:

1. Ensure no tables use vardecimal storage. Confirmed.
2. Set recovery mode to simple and do full backup. I did this.

But none of this makes any difference either. The option is still on and I can't change it.

Both instances of SQL Server are Express Edition (which isn't supposed to support Vardecimal Storage Format anyway).

Any ideas on how to turn this option off?

Answer 1

The vardecimal is a red herring because you can't downgrade a database whether this setting is true, false or non-existent. It's been asked before: Another question and again

Vardecimal is deprecated in SQL Server 2008 and has been replaced by compression of rows/tables.