CODEWITHSUNDEEP
c#entity-framework-4edmx
WheretheresaWill
WheretheresaWill

Reputation: 6480

Entity Framework 4.0 mapping issues

I'm getting the following error when trying to run a solution using Entity Framework 4.0 and am wondering how to change the mapping settings to correct it:

Problem in mapping fragments starting at line 588: Must specify mapping for all key properties (UserDatas.Id) of the EntitySet UserDatas

To give some background - I originally created the tables shown below with Modified/Created Date/By and Id columns in each of them, but then decided to pull them out into the abstract UserData and then use inheritance instead. Since I changed this it's all gone to pot!

Does anyone have any pointers as to where I'm going wrong? I've been using the design view show below (the GUI) and it feels like I've hit a brick wall.

My db.edmx design view looks like this, and clicking on the error takes me to the Variables table shown below, but the error is repeated for all the other tables that inherit this Id (please ignore all the links to other tables - I didn't want to post the whole big db schematic):

enter image description here

Many thanks.

Upvotes: 0

Views: 131

Answers (1)

Jim Wooley
Jim Wooley

Reputation: 10398

Sounds like you are mis-using OO inheritance here. Just because objects share items with the same property names doesn't mean that they Inherit from the base. For example, ask yourself in your modle if Tag IS A UserData? I suspect you could phrase this better that Tag HAS A UserData which points to containment rather than inheritance. I would recommend setting up a common IUserData interface where each object implements the interface distinctly. In that case, your mapping then would move the properties for the UserData interface back into the underlying classes (as they were configured originally). While you may be able to get your mapping to work with the inheritance model, your queries will get significantly complex both from a LINQ and TSQL perspective.

Upvotes: 1

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