Hi again, Nico. You're asking in the wrong group, so I'll reply even though
I am the wrong person to answer (I know virtually nothing about foreign
keys in IB).

>Should I define those 6 foreign keys?

If they're only accessed through your program(s), I wouldn't bother with
it. If you use TIB_LookupCombo, your users are restricted to what is in
there, anyway.

>Or could I have a performance problem after that??

Probably not. If your program is too slow to start with, you may increase
your problem by creating foreign keys, but six foreign keys by themselves
in a well-behaving program shouldn't create problems.

>Is foreign keys a good thing to use?

I don't think there's anything inherently wrong with foreign keys (if so,
you would have had plenty of replies by now).

Set