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From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-sql@postgresql.org
Subject: Re: Postgresql & Oracle Heteregenous services - strange behaviour
Date: Wed, 17 Jan 2007 07:58:57 -0500
Message-ID: <20070117125857.GD19527@phlogiston.dyndns.org> (raw)
In-Reply-To: <pan.2007.01.17.12.52.25.379331@gmail.com>
References: <pan.2007.01.17.12.52.25.379331@gmail.com>

On Wed, Jan 17, 2007 at 01:52:25PM +0100, Marcin St?pnicki wrote:
> I see this in postgresql logs:
> 
> [6210]   DEBUG:  query: select * from "zew_patients"
> [6210]   DEBUG:  query:  SELECT "A1"."p_nr_pesel" FROM "zew_patients"
> "A1" WHERE ("A1"."p_patient_id" = 19300)
> 
> The point is, I don't why oh why the first select is issued (some cache?),

<speculation level="rank">

I bet it's getting the column list from the table or some such thing. 
This is a lousy way to do it (the information_schema would be more
correct, although maybe no faster).

The reason it isn't repeated, I bet, is that your connection is
persistent, so the information gets cached.

</speculation>

A
-- 
Andrew Sullivan  | ajs@crankycanuck.ca
Everything that happens in the world happens at some place.
		--Jane Jacobs 



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