Re: pro- foreign key propaganda?

From: David Cressey <>
Date: Fri, 23 May 2008 11:17:20 GMT
Message-ID: <4JxZj.8796$bG1.986_at_trndny04>

"Brian Selzer" <> wrote in message news:Q8ZYj.24$
> "paul c" <toledobysea_at_ac.ooyah> wrote in message
> news:9eYYj.285346$pM4.76072_at_pd7urf1no...
> > Brian Selzer wrote:
> > ...
> >> I don't think the choice has anything to do with the desired or
> >> interpretation. The information contained within a database is the
> >> regardless of which candidate key is designated to be the primrary key.
> >> As far as the logic is concerned, the choice is completely arbitrary.
> >> That's not to say that there may not be a sound reason to choose one
> >> another: just that that reason is a matter of implementation, not
> >> interpretation.
> >> ...
> >
> > Saying that a choice is arbitrary yet not psychological is the most
> > magical kind of mysticism.
> I didn't say that it is not necessarily psychological. I said that it had
> nothing to do with the desired or intended interpretation. What does
> psychology have to do with the fact that sometimes you pull the middle
> from the left hand side of a fresh six-pack and sometimes the nearest from
> the right hand side? Are we supposed to read something into the fact that
> once in a while you pull the beer furthest away from you on the right-hand
> side? The beer closest to you should taste just as good as the one
> away. The choice of which candidate key is to be primary has as much to
> with the intended interpretation as the choice of which beer you pull
> out of a fresh six-pack has on how good it tastes.

There are discernable reasons for choosing one candidate key over another to be the primary key. Those reasons range from the number of bytes the candidate key takes up to the fear of key mismanagement by those who ultimately control that key data. Whether those reasons are or are not "psychological" is something I leave for the rest of you to determine. The decision is "arbitrary" only in the sense that the RDM would apply equally to the case at hand regardless of which choice is made. Received on Fri May 23 2008 - 13:17:20 CEST

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