How does ProviderManifestToken affect the database if the versions don't match?

We have a simple console app that uses EF 4 to process data; read from one, do some stuff, insert into another database. In the EDMX file, ProviderManifestToken for the destination db is set to "2005".

Yesterday, our app blew up. To make a long story short, our consultant says the db, which should be SQL Server 2000, was upgraded to 2005. That upgrade, according to them, was the reason for the app implosion. No one can explain how the upgrade occurred.

Can the value of ProviderManifestToken cause 开发者_JAVA百科an upgrade to the db? For example, if a db is currently 2000 and this app runs with "ProviderManifestToken = 2005", can that force an upgrade on the db? What happens, if anything at all, if the versions do not match?

Do you think that Entity framework contains installation DVD to upgrade your SQL Server 2000 to SQL Server 2005? No it doesn't. Provider manifest token only describes dialect (EF generates queries based on the dialect). It doesn't trigger any changes on the database. Somebody had to upgrade your database (upgrade to a new version is not free - you must have licence for that, it is not something downloaded through windows update).

Btw. SQL Server 2000 is not supported by EFv4 anyway. If you had your dialect set to 2005 and your solution worked with your database then it was 2005 all the time because linq-to-entities queries using First, Single, Take, Skip, etc. generated for 2005 dialect don't work on SQL Server 2000.