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Re: Help with Cartesian product

From: Billy Verreynne <vslabs_at_onwe.co.za>
Date: Mon, 23 Sep 2002 07:28:12 +0200
Message-ID: <amm8qv$rls$1@ctb-nnrp2.saix.net>


BackAt-Ya wrote:

> What's a Cartesian product

Joining tables without a join criteriia. In a two table cartersian join, row one of table 1 is joined with every single row in table 2. Ditto for every other row in table 1.

> and why or why wouldn't I want to use one?

It creates massive result sets.

Sometimes you need to use a cartersian join. Most often you do not and a cartesian join is a result of slipper fingers.

> Please give me some examples.

SELECT
  *
FROM table1,

     table2;

--
Billy
Received on Mon Sep 23 2002 - 00:28:12 CDT

Original text of this message

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