foreign keys - Entity framework code first - association on "polymorphic" columns -

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i have 3 tables:

1. invoice

invoiceid int primary key

2. order

orderid int primary key

3. transaction

transactionid int primary key

source int

category string

on table "transaction", source (unfortunately) behaving "polymorphic"(??) foreign key (there must actual term - sorry ignorance) depending on category column it'll contain id of invoice or order.

however there's no actual foreign key.

using ef 4.1 code first, has idea how create proper associations?

help appreciated! thanks

solution

uh... embarrassment kicking in... can map same way regardless of actual db foreign key.

i having problems while trying wasn't related this. had computation properties didn't ask context ignore generating wrong queries.

you should create 2 nullable fks instead of weak reference that.


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