Re: Question on COUNT performance

On Wed, Jul 14, 2010 at 07:30:39AM -0600, Joshua Tolley wrote:

> > Have you tried 'select count (1)..."?
>
> If this helps at all, it's unlikely to help much. I remember having seen
> discussion somewhere that there's an optimization such that count(*) and
> count(1) do the same thing anyway, but I can't find it in the code
> immediately.

oops, I was thinking too much about Sybase (where is makes a huge
difference, since the optimiser sees that everything it needs can be found
in the index so the table does not have to be read at all).

Reinoud

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Reinoud van Leeuwen reinoud(dot)v(at)n(dot)leeuwen(dot)net
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