Multiplicity constraint violated Entity framework 5

Question

Hello i have 3 classes Person, UserProfile(it inherits Person) and Results, a Person can have one or more results, when i try to add i a result to a person a i get the error

Answer 1

Are you trying to add the same Result to several users?

In that case this will fail because entity framework will realize the Results collection of the Person class as a foreign key from Results to Persons. The mapping will be the same as if you add a Person navigation property to the Result class.

If you want Person and Result to have a many-to-many relationship you have to add a ICollection<Person> Persons property to the Results class to make EF understand that.