From: David Fetter <shackle@fetter.org>
To: pgsql-sql@postgresql.org
Subject: Re: Optional join
Date: Fri, 15 Aug 2003 00:50:02 -0500
Message-ID: <nXidnVVfXr8X6aGiXTWc-w@speakeasy.net> (raw)
References: <sf3b6707.030@ems-t.ca>
"Slawek Jarosz" <Jarosz.S@ems-t.ca> wrote:
> Hi,
> I trying to write a query that will join 2 tables. Here's the
> concept:
> Table 1: table1, primary key pk1
> Table 2: table2, primary key pk2
> One of the fields (f2) in table2 contains either the primary key of
> table1 or a NULL value. So normally a pretty basic query:
> SELECT table1.*, table2.pk2
> FROM table1, table2 WHERE table2.f2 = table1.pk1;
> BUT what I would like to do is show all records of Table 1 even if
> there is no match in Table 2. Meaning that the reults could be
> table1... table2.pk2
> table1... NULL
> Doable?
Yes.
SELECT table1.*, table2.pk2
FROM table1 LEFT OUTER JOIN table2 ON (table1.pk1 = table2.pk2);
HTH :)
Cheers,
D
--
David Fetter david@fetter.org http://fetter.org/
phone: +1 510 893 6100 cell: +1 415 235 3778
Power over a man's subsistence is power over his will.
Alexander Hamilton
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To: pgsql-sql@postgresql.org
Cc: shackle@fetter.org
Subject: Re: Optional join
In-Reply-To: <nXidnVVfXr8X6aGiXTWc-w@speakeasy.net>
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