(I believe this is the same problem as this one, but there's no answer there, and I think I can express the problem better here...)
I have two Linq-to-SQL classes, State
and County
, where County
has a FK to State
. Here's some test code:
State s = State.GetState("NY"); // here I do a load of a State class via the Linq DataContext
County c = new County();
c.Name = "Rockland";
c.State = s;
MyDataContext.GetTable<County>().InsertOnSubmit(c);
MyDataContext.SubmitChanges(); // throws an exception
The exception thrown is "Violation of PRIMARY KEY constraint 'PK_State'. Cannot insert duplicate key in object 'dbo.State'"
.
In other words, what appears to be happening here is that despite my having loaded s
as an existing record, when I attempt to insert c
, Linq is assuming that all related objects, State
included, also need to be inserted!
This is completely absurd, and I cannot believe that Microsoft would have made such a huge blunder - so it must be that somewhere my own understanding is faulty.
Can anyone please explain what I am doing wrong, and what the correct approach here is?
Thanks!
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