Re: Meaning of 1:1, 1:1 generalization, 1:n, 1:n non identifying, n:m
Date: Wed, 13 Oct 2004 11:02:41 +0000 (UTC)
Message-ID: <ckj20h$6sp$1_at_titan.btinternet.com>
Joshua Beall wrote:
> Hi All,
It looks like a fabulous product, but there is a very bad bug in it: if
you add then remove a relationship between tables it will destroy the
the related key field in the 'destination' table.
>
> I've been taking a look at DB Designer 4, and looking through the
> documentation (http://www.fabforce.net/dbdesigner4/doc/index.html) I am a
> little unclear on some of their nomenclature:
>
> '1:1' - Ok, one to one. Got it.
> '1:1 generalization' - Don't know this. Obviously different somehow from
> one to one, but how?
> '1:n' - One to many, I assume.
> '1:n non identifying' - Nonidentifying? What does this mean?
> 'n:m' - Many to many? Again, not sure.
>
> Can anyone help clarify?
>
> Thanks!
> -Josh
>
>
Sorry I cant help drectly, but I would give a small warning to beware of
DB Designer 4...
I would debug and rebuild it myself, but I gave up on Delphi a few years ago and don't think I can be bothered to port it to Freepascal/Lazarus.
Mike Received on Wed Oct 13 2004 - 13:02:41 CEST