Re: count * performance issue

In response to "Robins Tharakan" <tharakan(at)gmail(dot)com>:

> Hi,
>
> I have been reading this conversation for a few days now and I just wanted
> to ask this. From the release notes, one of the new additions in 8.3 is
> (Allow col IS NULL to use an index (Teodor)).
>
> Sorry, if I am missing something here, but shouldn't something like this
> allow us to get a (fast) accurate count ?
>
> SELECT COUNT(*) from table WHERE indexed_field IS NULL
> +
> SELECT COUNT(*) from table WHERE indexed_field IS NOT NULL

For certain, qualified definitions of "fast", sure.

--
Bill Moran
Collaborative Fusion Inc.
http://people.collaborativefusion.com/~wmoran/

wmoran(at)collaborativefusion(dot)com
Phone: 412-422-3463x4023

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