Re: comparison of 8.3.10 to 8.3.14 reveals unexpected difference in explain plan

From: Mark Rostron <mrostron(at)ql2(dot)com>
To: Greg Smith <greg(at)2ndquadrant(dot)com>
Cc: "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: comparison of 8.3.10 to 8.3.14 reveals unexpected difference in explain plan
Date: 2011-02-14 04:40:20
Message-ID: FD020D3E50E7FA479567872E5F5F31E3046520C466@ex01.corp.ql2.com
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> It would be easier to suggest what might be wrong if you included "EXPLAIN ANALYZE" output instead of just EXPLAIN.
> It's not obvious whether 8.3 or 8.4 is estimating things better.

Thanks for reply man
Turns out random_page_cost was set low in the 8.3.10 version - when I reset it to 4(dflt), the explain plans are the same.
We'll double check our other queries, and then I'll see if I can reset it to dflt for the database.

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