Date: Tue, 29 Mar 2005 08:38:28 -0800 (PST)
From: Stephan Szabo <sszabo@megazone.bigpanda.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Simon Riggs <simon@2ndquadrant.com>,
 Karim A Nassar <Karim.Nassar@NAU.EDU>,
	Christopher Kings-Lynne <chriskl@familyhealth.com.au>,
	pgsql-performance@postgresql.org
Subject: Re: Delete query takes exorbitant amount of time 
In-Reply-To: <21616.1112108201@sss.pgh.pa.us>
Message-ID: <20050329083336.G58020@megazone.bigpanda.com>
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On Tue, 29 Mar 2005, Tom Lane wrote:

> Stephan Szabo <sszabo@megazone.bigpanda.com> writes:
> > If there were some way to pass a "limit" into SPI_prepare that was treated
> > similarly to a LIMIT clause for planning purposes but didn't actually
> > change the output plan to only return that number of rows, we could use
> > that.
>
> Hmm ... the planner does have the ability to do that sort of thing (we
> use it for cursors).  SPI_prepare doesn't expose the capability.
> Perhaps adding a SPI_prepare variant that does expose it would be the
> quickest route to a solution.
>
> I get a headache every time I look at the RI triggers ;-).  Do they

Me too, honestly.

> always know at the time of preparing a plan which way it will be used?

I believe so.  I think each saved plan pretty much lives for a single
trigger type/argument set and is basically used in only one place.