Re: a union is always a join!

From: rpost <>
Date: Tue, 7 Apr 2009 19:52:34 +0000 (UTC)
Message-ID: <grgau2$2gal$>

I just wrote

>[...] if you can point out which entity
>has changed, there must be some property or properties in the real
>world by which you made that identification, and those properties
>must be key attributes in your database model, so we should express the
>change in terms of changes to key attribute values and the identifier


>is superfluous. Makes sense, doesn't it.

Not much. I meant to say changes to other attributes.

Received on Tue Apr 07 2009 - 21:52:34 CEST

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