Re: why does this select hang postgres???

From: <pgsql-general(at)commandprompt(dot)com>
To: Jeremy Hansen <jeremy(at)xxedgexx(dot)com>
Cc: <pgsql-general(at)postgresql(dot)org>
Subject: Re: why does this select hang postgres???
Date: 2001-08-10 18:06:00
Message-ID: Pine.LNX.4.30.0108101104190.22311-100000@commandprompt.com
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On Fri, 10 Aug 2001, Jeremy Hansen wrote:
>select * from env_info,summary,plat_info;
>
>Is my statement broken? Is this not legal? Postgres just sits there....
>
>My goal is to select everything from multiple tables with one sql
>statement.

Well, without a JOIN or a WHERE clause, this query is going to try create
the raw cartesian product of the two tables. If you have a lot of data in
your tables, this might take a while, because it will return every
possible combination of rows.

Regards,
Jw
--
jlx(at)commandprompt(dot)com
by way of pgsql-general(at)commandprompt(dot)com

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