From: Peter Galbavy <peter.galbavy@knowtion.net>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-sql@postgresql.org
Subject: Re: 'fake' join and performance ?
Date: Tue, 22 Oct 2002 19:54:47 +0100
Message-ID: <000e01c279fc$7f33b5d0$10bc10ac@cblan.mblox.com> (raw)
References: <054501c279e5$8bfcfe00$4528a8c0@cblan.mblox.com>
<24033.1035308365@sss.pgh.pa.us>
> That would be in violation of the SQL spec. The query is defined to
> return each join row from the cross product of the FROM tables that
> meets the condition of the WHERE clause. As you wrote the query, each
> metadata row that meets the WHERE clause will be returned exactly as
> many times as there are rows in the images table. There is no such
> thing as an "unreferenced" FROM entry as far as SQL is concerned.
Sounds about right. Thanks for the clarification.
Peter
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To: pgsql-sql@postgresql.org
Cc: peter.galbavy@knowtion.net, tgl@sss.pgh.pa.us
Subject: Re: 'fake' join and performance ?
In-Reply-To: <000e01c279fc$7f33b5d0$10bc10ac@cblan.mblox.com>
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