EF Include() between contexts?

Question

I have two extended instances of DbContext that I use in my code-first solution. One is only ever read only as it maps to an existing set of tables for demographic purposes. The other context is mapped to a local working set of tables.

I have created a view and mapped it to its own entity that is included as a navigational property in a POCO model representing an entity that's mapped to the other context. So my question is: can I use Include to fetch related entities across contexts? So far this doesn't appear so as it complains that it's looking for the view under the wrong schema - the one used for the other context - even though the view clearly has the correct schema defined in its mapping.

I'm using EF 6 with MVC 4.

Answer 1

Each context runs in complete isolation and you cannot share objects from one context to the other. Even if you pull the objects from the database in notracking mode, the moment you associate those objects in the other context by assigning them to navigation properties you are effectively pulling them into the other context which you don't want.

If you have a readonly context of some kind then what you can do is only fill in the foreign keys ids in the read/write context.