Re: How would I write this query...

From: Ragnar <gnari(at)hive(dot)is>
To: Jim Fitzgerald <jfitz(at)spacelink(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: How would I write this query...
Date: 2006-05-01 16:22:11
Message-ID: 1146500531.11473.3.camel@localhost.localdomain
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On sun, 2006-04-30 at 11:32 -0700, Jim Fitzgerald wrote:
> I have two tables, one of them has names of people and an associated
> integer ID. The other table is a list of the people (from the first table)
> by their ID number that have signed up for a class. How would I write a
> query that would list all the people from the first table that do not have
> any entries in the second table? Basically, I want a listing of all my
> people who have not signed up for the class.

try

SELECT * FROM people LEFT JOIN classes using (peopleid)
WHERE classes.classid IS NULL;

gnari

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