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To: Thomas Kellerer <spam_eater@gmx.net>
Cc: pgsql-sql@postgresql.org
Subject: Re: SELECT very slow 
In-reply-to: <d87ood$8vq$1@sea.gmane.org> 
References: <d87ood$8vq$1@sea.gmane.org>
Comments: In-reply-to Thomas Kellerer <spam_eater@gmx.net>
	message dated "Wed, 08 Jun 2005 23:46:41 +0200"
Date: Wed, 08 Jun 2005 20:06:46 -0400
Message-ID: <27961.1118275606@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Thomas Kellerer <spam_eater@gmx.net> writes:
> Is there anything I can do, to convince PG to return the first row more 
> quickly?

libpq's API for PQresult is such that it really doesn't have any choice
but to collect the full result set before it hands you back the
PQresult.  I don't know JDBC very well but I think it has similar
semantic constraints.

The solution is to use a cursor and FETCH a reasonably small number of
rows at a time.

			regards, tom lane