Entity Framework 4 Error: Unable to update the EntitySet because it has a DefiningQuery

Question

Okay, here\'s the scenario. I have 3 tables. One called aspnet_Users one called Categories and a linking table called User_Categories. aspnet_Users and Categories both ha

Answer 1

I assume the full exception message is something similar to:

Unable to update the EntitySet YourTableName because it has a DefiningQuery and no InsertFunction element exists in the ModificationFunctionMapping element to support the current operation.

This will occur if your DB's table doesn't have a primary key defined.

Add a primary key to your table (using SQL Server Management Studio or whatever), and update your .edmx model from the database.