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From:SGreen Date:August 9 2004 3:44pm
Subject:Re: Selecting data from 2 tables.
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He does have a join. He has an *implied* INNER JOIN 
(http://dev.mysql.com/doc/mysql/en/JOIN.html): 

FROM pages, pdflog

What he is really missing is the WHERE clause that matches something from 
pages with something from pdflog....    Without it he is requesting a 
Cartesian product of his tables (every combination of each row from both 
tables). 

I prefer to define my JOINS *explicitly*. It makes it harder to 
accidentally define Cartesian products):

SELECT DISTINCT company
FROM pages
INNER JOIN pdflog
ON ...some condition goes here ....
ORDER BY company

Shawn Green
Database Administrator
Unimin Corporation - Spruce Pine

"Martijn Tonies" <m.tonies@stripped> wrote on 08/09/2004 11:38:31 AM:

> Hi,
> 
> > God, I feel real stupid this morning and know I should know this. I 
have
> > 2 tables in the same database and I'm trying to select distinct data 
from
> > a row with the same name in each table.
> >
> > SELECT DISTINCT company FROM pages, pdflog ORDER BY company ASC
> >
> > I'm missing something I'm sure because it doesn't work.
> 
> Feel stupid again ;-)
> 
> Where's your JOIN?
> 
> With regards,
> 
> Martijn Tonies
> Database Workbench - developer tool for InterBase, Firebird, MySQL & MS 
SQL
> Server.
> Upscene Productions
> http://www.upscene.com
> 
> 
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Thread
Selecting data from 2 tables.Ed Curtis9 Aug
  • Re: Selecting data from 2 tables.Martijn Tonies9 Aug
    • Re: Selecting data from 2 tables.Ed Curtis9 Aug
    • Re: Selecting data from 2 tables.SGreen9 Aug
      • Re: Selecting data from 2 tables.Ed Curtis9 Aug
      • Re: Selecting data from 2 tables.Ed Curtis9 Aug
        • Re: Selecting data from 2 tables.SGreen9 Aug
          • Re: Selecting data from 2 tables.Ed Curtis9 Aug
            • Re: Selecting data from 2 tables.SGreen9 Aug
      • Re: Selecting data from 2 tables.Martijn Tonies9 Aug