From: chester c young <chestercyoung@yahoo.com>
To: sql pgsql <pgsql-sql@postgresql.org>
Subject: problem join
Date: Thu, 26 Jul 2007 18:39:31 -0700 (PDT)
Message-ID: <820562.64742.qm@web54307.mail.re2.yahoo.com> (raw)
having problem joining these correctly:
schedule
- cal_id references calendar not null
- usr_id references users not null
= unique( calZ_id, usr_id )
- result_no not null
activity
- cal_id references calendar not null
- usr_id references users not null
= unique( cal_id, usr_id )
- from_ts timestamp not null
trying to join
- cal_id
- usr_id
- schedule.result_no (might be null)
- activity.from_ts (might be null)
where schedule.usr_id = activity.usr_id would result in one row
thanks for insight!
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To: pgsql-sql@postgresql.org
Cc: chestercyoung@yahoo.com
Subject: Re: problem join
In-Reply-To: <820562.64742.qm@web54307.mail.re2.yahoo.com>
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