Could not find the conceptual model type

Question

I have two Entity Data models within a MVC3 project A and B.

I have recently added the new entity data model B to deal with some new functionality, the issue is that now the existing code has stopped working and I am getting the following error when trying to access code within entity model A.

The error message is:

Could not find the conceptual model type 'project.models.Bclass'

I do not understand why it is this new functionality has affected the current code seeing as entity model A has not change in any way. And functionality B is in a separate class and does not interfere with model A.

When the new code is removed from the project and entity model B is excluded then the code works as it should.

Here is some of the stacktrace from the error:

Exception : Could not find the conceptual model type for 'Project1.Models.CrossSession'.
Application Class - method : System.Data.Metadata.Edm.MetadataWorkspace -- GetEdmSpaceType
User : temp.user
Url : http://localhost/project1/auth/message
Stacktrace :    at System.Data.Metadata.Edm.MetadataWorkspace.GetEdmSpaceType(StructuralType objectSpaceType)
   at System.Data.Entity.Internal.InternalContext.UpdateEntitySetMappings()
   at System.Data.Entity.Internal.InternalContext.TryUpdateEntitySetMappingsForType(Type entityType)
   at System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType)
   at System.Data.Entity.Internal.Linq.InternalSet`1.Initialize()
   at System.Data.Entity.Internal.Linq.InternalSet`1.get_InternalContext()

Answer 1

Well I just installed EF 4.1 and tried to combine DbContext with a EMDX - When I tried to pass back a view I got the same error - that's why I ended up here... I think the way around this is to separate the functionality out into separate asemblies in the solution...

Answer 2

Using Visual Studio 12, the issue has still not been resolved. As an alternative workaround, I set up the second SQL data model using "old fashioned" Data Classes that pre-date entity models - they're still there and they still work. Use Add - New Item - (Data Category) - LINQ To SQL Classes, open the ServerExplorer, locate the server and database, then drag and drop it onto the data classes pane. Old school - but conveniently overcomes this highly inconvenient issue when the full functionality of entity models is not needed.

Answer 3

Solution found. It appears in some cases (randomly) there is a mix up in the code generated by the entity framework. This is apparently a known bug and a fix should be coming in future releases. In the mean time the way around this is to move the efm to a separate class within the solution.

Answer 4

I removed the edmx models, removed the Entity package, re-install the entity 5.0 and works.

Answer 5

This can also be resolved by generating the new edmx in visual studio 2010 so it matches the older ones... (And copying over the files it generates)

Answer 6

I had the same problem with 2 different .edmx files in the same project. For the first .edmx model I had used "Add Code Generation Item", for the second model I hadn't. The project was building correctly but throwing that exception on runtime.

I solved generating the .tt classes for the second .edmx model as well.