Message-ID: <50ACD6B6.1030905@optionshouse.com>
Date: Wed, 21 Nov 2012 07:27:18 -0600
From: Shaun Thomas <sthomas@optionshouse.com>
Reply-To: <sthomas@optionshouse.com>
Organization: Peak6
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To: Craig Ringer <craig@2ndQuadrant.com>
CC: Craig James <cjames@emolecules.com>, Tom Lane <tgl@sss.pgh.pa.us>, Claudio
	Freire <klaussfreire@gmail.com>, Merlin Moncure <mmoncure@gmail.com>, David
	Greco <David_Greco@harte-hanks.com>, "pgsql-performance@postgresql.org"
	<pgsql-performance@postgresql.org>
Subject: Re: Hints (was Poor performance using CTE)
References: 
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	<50AC3935.6060508@2ndQuadrant.com>
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On 11/20/2012 08:15 PM, Craig Ringer wrote:

> I think it's time to admit that and get the syntax in place for CTEs so
> there's room to optimize them later, rather than cementing
> CTEs-as-fences in forever as a Pg quirk.

I know I'm just some schmo, but I'd vote for this. I'm certainly guilty 
of using OFFSET 0. Undocumented hints are still hints. As much as I 
think they're a bad idea by cementing a certain plan that may not get 
the benefits of future versions, non-intuitive side-effects by using 
overloaded syntax are worse.

I've been using CTEs as temp tables because I know that's how they work. 
But I'd be more than willing to modify my syntax one way or the other to 
adopt non-materialized CTEs, provided there's some way to get the 
current behavior.

-- 
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604
312-444-8534
sthomas@optionshouse.com

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