Re: [HACKERS] Much Ado About COUNT(*) - Mailing list pgsql-general

From Csaba Nagy
Subject Re: [HACKERS] Much Ado About COUNT(*)
Date
Msg-id 1105627731.14493.18.camel@localhost.localdomain
Whole thread Raw
In response to Re: [HACKERS] Much Ado About COUNT(*)  (Greg Stark <gsstark@mit.edu>)
Responses Re: [HACKERS] Much Ado About COUNT(*)  (Greg Stark <gsstark@mit.edu>)
List pgsql-general
[snip]
> The database could be clever and implement the same kind of sampling vacuum
> does. That picks a random sampling of pages from the table without using an
> index. But there's no way to implement the same kind of behaviour from the
> user-visible features.
... meaning perhaps a new keyword accepted by SELECT, something like
"SAMPLE 1000" ? Which would mean sample records in a 1:1000 ratio ?
Would simplify (and probably speed up a lot) some estimating queries...

Cheers,
Csaba.



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