I sent this message to the list and although it shows up in the archives,
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---------- Forwarded message ----------
Date: Sat, 13 Mar 2004 22:48:01 -0500 (EST)
From: Kris Jurka <[EMAIL PROTECTED]>
Subject: Re: [PERFORM] severe performance issue with planner 

On Thu, 11 Mar 2004, Tom Lane wrote:

> "Eric Brown" <[EMAIL PROTECTED]> writes:
> > [ planning a 9-table query takes too long ]
> See http://www.postgresql.org/docs/7.4/static/explicit-joins.html
> for some useful tips.

Is this the best answer we've got?  For me with an empty table this query 
takes 4 seconds to plan, is that the expected planning time?  I know I've 
got nine table queries that don't take that long.

Setting geqo_threshold less than 9, it takes 1 second to plan.  Does this 
indicate that geqo_threshold is set too high, or is it a tradeoff between 
planning time and plan quality?  If the planning time is so high because 
the are a large number of possible join orders, should geqo_threhold be 
based on the number of possible plans somehow instead of the number of 
tables involved?

Kris Jurka

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