Re: [GENERAL] JOIN exclusion problem - Mailing list pgsql-general

From Peter Eisentraut
Subject Re: [GENERAL] JOIN exclusion problem
Date
Msg-id Pine.LNX.4.10.9906301401040.30903-100000@uruguay.pathwaynet.com
Whole thread Raw
In response to JOIN exclusion problem  (Anja Speerforck <anja@damn.com>)
List pgsql-general
On Wed, 30 Jun 1999, Anja Speerforck wrote:

> Hello,
>
> I'm trying to join three tables, where I need only one piece of data from
> two of the tables.  The code I wrote is:
>
> SELECT apartner_nr, ap.anrede, ap.vorname, ap.nachname, ap.telefon, ap.fax,
> ap.email, ap.kunden_nr, k.name1, ap.agentur_nr, ag.name1
> FROM ansprechpartner ap, kunden k, agenturen ag
> WHERE ap.kunden_nr = k.kunden_nr OR ap.agentur_nr = ag.agentur_nr
                                   ^^
You might wanna try an AND there.

> ORDER BY nachname"
>
> The problem is that each row from each table is combined with each row of
> the other tables.  I know the code is wrong, but I don't know how to write
> it so that the results show only the actual value of ag.name1 and k.name1,
> and not all of the possible combinations.
>
> Is there a way of limiting how the rows are built up?  Pardon for novice
> nature of this question...

--
Peter Eisentraut
PathWay Computing


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