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Re: So what's null then if it's not nothing?

From: Jon Heggland <heggland_at_idi.ntnu.no>
Date: Fri, 25 Nov 2005 16:10:41 +0100
Message-ID: <MPG.1df147db4b9576998970e@news.ntnu.no>


In article <1132926804.625596.34020_at_g47g2000cwa.googlegroups.com>, boston103_at_hotmail.com says...
>
> michael_at_preece.net wrote:
> [...]
> >
> > Any two variables/"fields" (of any type) with "no value at all" are,
> > indeed, equal.
> >
> > Mike.
>
> Cute.

"Cute"?

> So, using your valuation for equality, would a query asking for a
> pairwise list of people living in the same country produce a correct
> result if some pairs that happen to have nulls for their countries ?

That, of course, depends on what you mean by a correct result, what it means that country is NULL, and how the query is formulated.

If we assume that it is not generally the case that two people with NULLs for their countries (speaking loosely here) live in the same country, the query would simply have to be written so as to disregard people with NULL country.

-- 
Jon
Received on Fri Nov 25 2005 - 09:10:41 CST

Original text of this message

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