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In-Reply-To: <4A3807CF.90109@consumercontact.com>
References: <4A3807CF.90109@consumercontact.com>
Date: Tue, 16 Jun 2009 14:25:44 -0700
Message-ID: <396486430906161425i1cb7949enff5443cc2043805a@mail.gmail.com>
Subject: Re: left outer join on more than 2 tables?
From: Richard Broersma <richard.broersma@gmail.com>
To: Carol Cheung <cacheung@consumercontact.com>
Cc: pgsql-sql@postgresql.org
Content-Type: text/plain; charset=ISO-8859-1
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On Tue, Jun 16, 2009 at 1:59 PM, Carol
Cheung<cacheung@consumercontact.com> wrote:
> I would like to find the counts of complaints by region and I would like all
> regions to be displayed, regardless of whether or not complaints exist for
> that region. Is left outer join what I'm looking for?

   SELECT R.region_name, Count(*) AS RegionComplaints
     FROM Region AS R
LEFT JOIN City AS Ci
       ON R.id = C.region_id
LEFT JOIN Complaint AS Cm
       ON Ci.id = Cm.city_id
 GROUP BY R.region_name;


-- 
Regards,
Richard Broersma Jr.

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