Re: Re: BETWEEN [SYMMETRIC | ASYMMETRIC]

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От Thomas Swan
Тема Re: Re: BETWEEN [SYMMETRIC | ASYMMETRIC]
Дата
Msg-id 5.0.2.1.0.20010111084710.01ad7580@tangent.ics.olemiss.edu
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Ответ на Re: Re: BETWEEN [SYMMETRIC | ASYMMETRIC]  (Tom Lane <tgl@sss.pgh.pa.us>)
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At 1/10/2001 09:10 PM, you wrote:
>Thomas Swan <tswan-lst@ics.olemiss.edu> writes:
> > Actually if it were possible to look at the values before expanding.  You
> > could reorder the expression so that it was always the case that B < C,
> > then your cost would only be one comparison plus the sequential scan.
>
>Uh ... what if B and C are not constants?

Hmmm... I see your point.  I was looking back through the sources and was 
thinking.

I'd hate doing the work twice.

Is there something in place to reorder or sort or compare results?
Possibly expanding to something like a <= max(b,c) and a >= min(b,c)





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