From: Phillip Smith <phillip.smith@weatherbeeta.com.au>
To: 'Colin Wetherbee' <cww@denterprises.org>
To: pgsql-sql@postgresql.org
Subject: Re: JOIN a table twice for different values in the same query
Date: Fri, 11 Jan 2008 09:23:12 +1100
Message-ID: <002f01c853d7$63bc0680$9b0014ac@wbaus090> (raw)
In-Reply-To: <47869704.8050306@denterprises.org>
Try something like this where we alias the joined tables:
SELECT departure_date,
j1.code AS departure_code,
j2.code AS arrival_code
FROM jsjourneys
LEFT OUTER JOIN jsports AS j1 ON jsjourneys.departure_port = j1.id
LEFT OUTER JOIN jsports AS j2 ON jsjourneys.arrival_port = j2.id;
As a side note - all the IATA codes are unique for each airport - wouldn't
it be better to use these as the Primary Key and Foreign Keys? Then you
wouldn't have to even join the tables unless you wanted the port names (not
just the code)
Cheers,
~p
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To: pgsql-sql@postgresql.org
Cc: phillip.smith@weatherbeeta.com.au, cww@denterprises.org
Subject: Re: JOIN a table twice for different values in the same query
In-Reply-To: <002f01c853d7$63bc0680$9b0014ac@wbaus090>
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