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Re: Various performance questions

From: Christopher Browne <cbbrowne(at)acm(dot)org>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Various performance questions
Date: 2003-10-27 12:52:06
Message-ID: m3isman8qx.fsf@wolfe.cbbrowne.com (view raw or flat)
Thread:
Lists: pgsql-performance
In the last exciting episode, dror(at)zapatec(dot)com (Dror Matalon) wrote:
> I was answering an earlier response that suggested that maybe the actual
> counting took time so it would take quite a bit longer when there are
> more rows to count.

Well, if a "where clause" allows the system to use an index to search
for the subset of elements, that would reduce the number of pages that
have to be examined, thereby diminishing the amount of work.

Why don't you report what EXPLAIN ANALYZE returns as output for the
query with WHERE clause?  That would allow us to get more of an idea
of what is going on...
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Next:From: Greg StarkDate: 2003-10-27 15:09:09
Subject: Re: Various performance questions
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Subject: Re: Performance Concern

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