Can I mix Table per Hierarchy and Table per Type in Entity Framework?
Say I have 2 tables: Message and SuperMessage
and 3 entities: Message (base (not abstract)), Comment (inherits from Message) and SuperMessage (inherits from Message)
Message has a non-nullable MessageType field which is used as a discriminator.
The problem is that I cannot specify a condition on MessageType of the SuperMessage's Mapping details section because it cannot see the MessageType field and I cannot ignore it.
How can I make these work alongside eachother?
UPDATE Build Error:
Error 3014: Problem in mapping fragments:The foreign key 'Foreign key constraint 'FK_SuperMessage_inherits_Message' from table SuperMessage (ID) to table Message (MessageId):' is not being enforced in the model. An Association or inheritance relationship needs to be created to enforce this constraint.
I reproduced this and got the same error as you. As far as I can tell, it appears that combining these two types of inheritance for a single base table is just not possible. I'd love to be proved wrong though. ;-)
Have you tried adding an intermediate abstract entity type, ie:
abstract MessageBase --> Message table
non-abstract Message --> Message table when MessageType == 1
non-abstract Comment --> Message table when MessageType == 2
abstract SuperMessageBase --> Message table when MessageType == 3
non-abstract SuperMessage --> SuperMessage table
Also check out a similar scenario I solved: EF: Can I mix TPH and TPT when abstract base and a few concrete types are in TPH-table and other types have their own table?
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