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Re: object algebra

From: Neo <neo55592_at_hotmail.com>
Date: 28 Feb 2004 20:53:30 -0800
Message-ID: <4b45d3ad.0402282053.5107b3e0@posting.google.com>


> > Given EyeColor = {red, brown, NOT_APPLICABLE}
> > Given the table:
> > Person EyeColor
> > ------ --------------
> > Mary NOT_APPLICABLE
> > Bob NOT_APPLICABLE
> >
> > Then, Mary.EyeColor equals Bob.EyeColor leading an AI[type] program to
> > conclude that Mary and Bob have the same EyeColor.
>
> All of Bob's eyes have the same color as all of Mary's eyes.
> What is the problem?

This exemplifies Date's observation on p586: "3VL suffers from the very serious ("showstopper") problem that it does not match reality - that is, results that are correct according to 3VL are sometimes incorrect in the real world". Received on Sat Feb 28 2004 - 22:53:30 CST

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