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Re: Key attributes with list values was Re: What are the differences ...KEY

From: Brian Selzer <brian_at_selzer-software.com>
Date: Mon, 27 Feb 2006 17:50:53 GMT
Message-ID: <1_GMf.16932$2O6.6928@newssvr12.news.prodigy.com>


The name certainly does provide logical identity with respect to a single database state, and it is indeed a natural key. But natural key values are mutable; consequently, the logical identity one provides is not guaranteed to be the same in more than one database state. Hence the need for a second immutable key.

"Anith Sen" <anith_at_bizdatasolutions.com> wrote in message news:dtvcju$b64$1_at_emma.aioe.org...
>>> By revealing an attribute that reflects the identity of a proposition
>>> with respect to all other propositions in the database.
>
> So since name provides no logical identity, it is not the key as you
> stated before, right?
>
> --
> Anith
>
Received on Mon Feb 27 2006 - 11:50:53 CST

Original text of this message

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