I am writing two MVC5 (with EF6 and code-first) web apps using generic UnitOfWork that gets the dbContext injected by Unity.
We are required to have two databases (
The easiest approach would be to link tables from one database to the other so that this is the database server which handles two physical databases as one virtual database.
Then, in EF, you have just one context with tables from both databases and querying/joins etc. works correctly.
http://msdn.microsoft.com/en-us/library/ff772782.aspx
Otherwise, linking two databases in the application layer with EF and two contexts sounds impossible.