From: Gavin Baumanis <gavinb@eclinic.com.au>
To: Richard Broersma <richard.broersma@gmail.com>
Cc: Carol Cheung <cacheung@consumercontact.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: left outer join on more than 2 tables?
Date: Wed, 17 Jun 2009 07:39:50 +1000
Message-ID: <E8B4F516-1647-4621-B744-5DB66E1EC682@eclinic.com.au> (raw)
In-Reply-To: <396486430906161425i1cb7949enff5443cc2043805a@mail.gmail.com>
References: <4A3807CF.90109@consumercontact.com>
<396486430906161425i1cb7949enff5443cc2043805a@mail.gmail.com>
At the risk of being wrong.... (I'm always ready to learn something
new) - and seemingly I'm only too happy to be wrong!...
And... it might even be that it is exactly the same result - but I
would have proposed;
SELECT
R.region_name,
Count(*) AS RegionComplaints
FROM
Region AS R
LEFT JOIN City AS Ci
LEFT JOIN Complaint AS Cm ON Ci.id = Cm.city_id
ON R.id = C.region_id
GROUP BY
R.region_name;
Gavin.
On 17/06/2009, at 7:25 AM, Richard Broersma wrote:
> 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.
>
> Visit the Los Angeles PostgreSQL Users Group (LAPUG)
> http://pugs.postgresql.org/lapug
>
> --
> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
> To make changes to your subscription:
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As always Please contact me if I can be of any further assistance.
Gavin "Beau" Baumanis
Senior Application Developer
PalCare P/L
657 Nicholson Street
Carlton North
Victoria, Australia, 3054
E: beau@palcare.com.au
P: +61 -3 9380 3513
M: +61 -438 545 586
W: http://www.palcare.com.au
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To: pgsql-sql@postgresql.org
Cc: gavinb@eclinic.com.au, richard.broersma@gmail.com, cacheung@consumercontact.com
Subject: Re: left outer join on more than 2 tables?
In-Reply-To: <E8B4F516-1647-4621-B744-5DB66E1EC682@eclinic.com.au>
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