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From:Gerald L. Clark Date:June 30 2006 2:54pm
Subject:Re: Multiple joins
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Steffan A. Cline wrote:
> What am I missing here?
> 
> select m.*, d.discussion, d.discussion_id, u.user_id, t.topic_id
> from forums_messages
> left join forums_members m, forums_discussions d, users u, forums_topics t
> on m.topic_id = t.topic_id, t.discussion_id = d.discussion_id
> where m.topic_id = "1";
> 
> Is it legal to do multiple joins like this?
> 
> 
> 
> 
> Thanks
> 
> Steffan


forum_messages does not take part in any selection or any where clause.
You have 5 tables listed, with only 4 of them appearing in 2 disjointed, 
and improperly formed joins.
 From the comma separated table list after a LEFT JOIN, I am not sure
whether you intend them to be LEFT JOINs or INNER JOINs.

Try:
SELECT fields
FROM file1
LEFT JOIN file2 ON something
INNER JOIN file3 ON something
INNER JOIN file4 ON something
INNER JOIN file5 ON something
WHERE somecondition




-- 
Gerald L. Clark
Supplier Systems Corporation
Thread
Multiple joinsSteffan A. Cline30 Jun
  • Re: Multiple joinsGerald L. Clark30 Jun
    • Re: Multiple joinsSteffan A. Cline30 Jun
  • Re: Multiple joinsBrent Baisley30 Jun