Entity Framework 4 - TPH Inheritance in Features CTP5 (code first) with “IS NULL” discriminator

Question

Hey guys, I\'m trying to create a TPH mapping on a hierarchy where the discriminating clause is the classical \"IS NOT NULL\" / \"IS NULL\" case.

Here is the example, da

Answer 1

Unfortunately, having a null value for the discriminator column in TPH mapping is not currently supported in CTP5. This is confirmed by EF team on here and also here. They are looking at it to see if they can make it work for the RTM though.