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Re: Really dumb planner decision

From: Matthew Wakeling <matthew(at)flymine(dot)org>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Merlin Moncure <mmoncure(at)gmail(dot)com>, Grzegorz Jaśkiewicz <gryzman(at)gmail(dot)com>, pgsql-performance(at)postgresql(dot)org
Subject: Re: Really dumb planner decision
Date: 2009-04-16 15:54:49
Message-ID: alpine.DEB.2.00.0904161651420.4053@aragorn.flymine.org (view raw or flat)
Thread:
Lists: pgsql-performance
On Thu, 16 Apr 2009, Robert Haas wrote:
> I hasten to point out that I only suggested raising them to the moon
> as a DEBUGGING strategy, not a production configuration.

The problem is that we have created a view that by itself a very 
time-consuming query to answer, relying on it being incorporated into a 
query that will constrain it and cause it to be evaluated a lot quicker. 
This kind of scenario kind of guarantees a bad plan as soon as the number 
of tables reaches from_collapse_limit.

Matthew

-- 
 Failure is not an option. It comes bundled with your Microsoft product. 
                                                 -- Ferenc Mantfeld

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