Re: An unwanted seqscan

[Brian Herlihy <btherl(at)yahoo(dot)com(dot)au>]

Hi Tom,

Sorry, I didn't ask the right question.  I meant to ask "Why does it estimate a smaller cost for the seqscan?"

With some further staring I was able to find the bad estimate and fix it by increasing the relevant statistics target.

Thanks,
Brian

----- Original Message ----
From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Brian Herlihy <btherl(at)yahoo(dot)com(dot)au>
Cc: Postgresql Performance <pgsql-performance(at)postgresql(dot)org>
Sent: Wednesday, 14 February, 2007 4:53:54 PM
Subject: Re: [PERFORM] An unwanted seqscan 

Brian Herlihy <btherl(at)yahoo(dot)com(dot)au> writes:
> I am having trouble understanding why a seqscan is chosen for this query.

As far as anyone can see from this output, the planner's decisions are
correct: it prefers the plans with the smaller estimated cost.  If you
want us to take an interest, provide some more context --- EXPLAIN
ANALYZE output for starters.

            regards, tom lane

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