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Date: Mon, 28 Oct 2002 19:53:52 -0800 (PST)
From: Stephan Szabo <sszabo@megazone23.bigpanda.com>
To: Josh Berkus <josh@agliodbs.com>
Cc: <pgsql-sql@postgresql.org>
Subject: Re: BOOLEAN question
In-Reply-To: <200210281729.35967.josh@agliodbs.com>
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On Mon, 28 Oct 2002, Josh Berkus wrote:

> Stephan,
>
> > Well, you might be better off making a max(bool), but a not
> > super-efficient version might be:
> >  max(case when col then 1 else 0 end)=1
>
> Good, I'm not just brain-dead.   I did figure out another way to do it, but if
> I wrote a MAX(bool), what are the chances it would get added to the core?   I
> don't see any good reason not to have one.

Don't know really.  I guess if we're saying that true>false it might
make sense, although the notion of max(bool) seems odd to me, especially
since it only easily handles an ANY case.

Speaking of which, a more expensive but possibly nicer looking way would
be something like
true=ANY(select col from <whatever>)

(which of course also generalizes into =ALL fairly easily)