> Hi,
> 
> I have a somewhat large table, 3 million rows, 1 Gig on disk,  and growing. Doing a
> count(*) takes around 40 seconds.
> 
> Looks like the count(*) fetches the table from disk and goes through it.
> Made me wonder, why the optimizer doesn't just choose the smallest index
> which in my case is around 60 Megs and goes through it, which it could
> do in a fraction of the time.
> 
> Dror

Just like other aggregate functions, count(*) won't use indexes when 
counting whole table.

Regards,
Tomasz Myrta

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• count(*) slow on large tables at 2003-10-02 19:15:47 from Dror Matalon

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