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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Craig James <cjames@emolecules.com>
cc: Joe Conway <mail@joeconway.com>,
	Heikki Linnakangas <hlinnakangas@vmware.com>,
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Subject: Re: Hints (was Poor performance using CTE)
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Comments: In-reply-to Craig James <cjames@emolecules.com>
	message dated "Wed, 21 Nov 2012 09:28:35 -0800"
Date: Wed, 21 Nov 2012 12:39:46 -0500
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Craig James <cjames@emolecules.com> writes:
> On Wed, Nov 21, 2012 at 9:25 AM, Joe Conway <mail@joeconway.com> wrote:
>> I like this idea, but also think that if we have a syntax to allow
>> hints, it would be nice to have a simple way to ignore all hints (yes, I
>> suppose I'm suggesting yet another GUC). That way after sprinkling your
>> SQL with hints, you could easily periodically (e.g. after a Postgres
>> upgrade) test what would happen if the hints were removed.

> Or a three-way choice: Allow, ignore, or generate an error.  That would
> allow developers to identify where hints are being used.

Throwing errors would likely prevent you from reaching all parts of your
application, thus preventing complete testing.  Much more sensible to
just log such queries.

			regards, tom lane