>Well, the truth is I am trying to get my head around Entity Framework, so I need a database designed the way it "is done", as opposed to, as would say I guess, the way it makes sense :).
>
>I thought I had _the_ application with quintescencial simplicity, and here I am faced with a "complex" relation I doubt I'll be able put down EF's throat.
>
>Ah well. It takes time for an old dog (fox?) to change his ways.

Well if you have the time and patience, you may still do it in the insert trigger of the transaction record. Have a function which creates a PK, call it for transaction and stockitem record, assign as PK and FK into each, then allow save.