From: Josh Berkus <josh@agliodbs.com>
To: vampyre5@yahoo.com
To: pgsql-sql@postgresql.org
Subject: Re: Help with query involving aggregation and joining.
Date: Sun, 23 Feb 2003 12:24:47 -0800
Message-ID: <200302231224.47583.josh@agliodbs.com> (raw)
In-Reply-To: <20030223190227.21867.qmail@web80401.mail.yahoo.com>
References: <20030223190227.21867.qmail@web80401.mail.yahoo.com>
Eddie,
> My requirements involve several large tables. I have
> simplied scenario into the follow two fictional tables
> which describes the same requirements.
Keep in mind that a simplified example may not solve your real problem ...
> Basically I would like to display the latest
> submission for each course in a table as shown below,
> order by name of the courses.
>
> Query Results:
> ==============
> id | courseId | name | submission
> ---------------------------------------
> 4 | 102 | Chemisty | 2002-02-22
> 3 | 104 | Maths | 2002-04-30
> 1 | 101 | Physics | 2002-01-20
Easy:
SELECT id, courseid, name, max(submission) as submission
FROM history JOIN courses ON history.courseid = course.id
GROUP BY id, courseid, name
ORDER BY name
And as such, I suspect that your real case is more complicated than the above
...
--
Josh Berkus
Aglio Database Solutions
San Francisco
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To: pgsql-sql@postgresql.org
Cc: josh@agliodbs.com, vampyre5@yahoo.com
Subject: Re: Help with query involving aggregation and joining.
In-Reply-To: <200302231224.47583.josh@agliodbs.com>
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