Re: why does this select hang postgres???

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Тема Re: why does this select hang postgres???
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Msg-id Pine.LNX.4.30.0108101104190.22311-100000@commandprompt.com
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Ответ на why does this select hang postgres???  (Jeremy Hansen <jeremy@xxedgexx.com>)
Ответы Re: why does this select hang postgres???  (<pgsql-general@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@commandprompt.com
by way of pgsql-general@commandprompt.com



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