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Re: Negative Numbers in "Identity" or" Autonumber" fields

From: Cimode <cimode_at_hotmail.com>
Date: 21 Mar 2007 06:49:08 -0700
Message-ID: <1174484948.747256.3330@b75g2000hsg.googlegroups.com>


On Mar 21, 2:33 pm, "JOG" <j..._at_cs.nott.ac.uk> wrote:
> On Mar 21, 6:46 am, "Marshall" <marshall.spi..._at_gmail.com> wrote:
>
> > On Mar 20, 10:31 am, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>
> > > [...] Nothing in a
> > > proposition should ever be hidden from the user. Propositions come
> > > from outside of the logical layer after all. If an attribute is an
> > > identifier then it clearly impacts on identifying items in the real
> > > world.
>
> > I buy the "nothing should be hidden" argument, but I can't
> > decide if a domain that only supports equality is hiding
> > anything or not.
>
> > Marshall
>
> I'm not sure I'm entirely clear what you mean by a domain that only
> supports equality Marshall. If we are creating a surrogate that only
> exhibits equality with some other attribute... well (outside of some
> physical use for indexing say), what would be the point of having
> created it in the first place? It has to have some added value
> logically in my book. Although I might have got the wrong end of the
> stick. regards, J.

I am curious about this statement. Why would believe that relating surrogate keys to domain definition should be done through restriction of possible operators applyable. It is a shortcut that seems both interresting and dangerous to me.

Regards... Received on Wed Mar 21 2007 - 08:49:08 CDT

Original text of this message

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