Re: One to One Relationship

Following up on Paul Brewer, 20 Mar 2003:

>
> I don't disagree with any of this, nor with other examples posted, but
> these are *physical* considerations.

Sure, but subtyping isn't. It can serve a very specific logical purpose. I think the old books on Case Designer had a good description of where, but I can't find mine anywhere!

> Earlier in this thread, I suggested that they are *logically* the same
> table, and recommended that OP do the logical design before moving on to
> physical considerations.

Absolutely! In fact, my feeling is that the OP was talking about a true 1:M case, not 1:1 at all. He was just getting mixed up.

>
> I concede, however, that I may have put it somewhat abruptly.

Hey! No problems with that, as far as I'm concerned! :) The reason I entered the thread is that I felt true 1:1 was being set aside as a "no-no". Which I feel is not the case: most subtypes are 1:1, if not all. So, I gave a few examples of where it is useful.

-- 
Cheers
Nuno Souto
wizofoz2k_at_yahoo.com.au.nospam