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Re: sql return only first matching record from join table

From: Barnoit <jbarney_ca_at_yahoo.ca>
Date: 3 Jul 2002 18:47:37 -0700
Message-ID: <cd2c60c8.0207031747.2eaf15f6@posting.google.com>


I've figured it out, but I've also created a new problem. I'm now using
... and occupant.rowid IN (SELECT MIN(occupant.rowid) FROM occupant GROUP BY occupant.key_id)
which actually does what I want, however what I really need is this: ... and occupant.rowid(+) IN (SELECT MIN(occupant.rowid) FROM occupant GROUP BY key_id) *note the outer join*. This is not valid in oracle (can't have an outerjoin with a subquery). To make things more complicated from my original post, the query actually checks 2 tables for the occupant name, and if it doesn't exist in one I need to check the other, hence the outer join. The way the query is written, I actually return them both in the select statement, and I have some external logic to grab the appropriate value. Is there another way to do this outer join on a subquery?

Thanks   

"Richard Foote" <richard.foote_at_bigpond.com> wrote in message news:<IBDU8.26883$Hj3.82905_at_newsfeeds.bigpond.com>...
> Hi Barnoit,
>
> Simply add 'and rownum=1' to the where condition. Oracle will then only
> return the first row that meets the other conditions.
>
> Good Luck
>
> Richard
> "Barnoit" <jbarney_ca_at_yahoo.ca> wrote in message
> news:cd2c60c8.0207030600.39d024b8_at_posting.google.com...
> > Just to simplify my example, I have 2 tables that are joined on a key
> > id (there are actually quite a few joins, but this is the one causing
> > me trouble). The keyid on the first table is unique, but there is a
> > one to many relationship in the second table (it is actually a street
> > address table and an occupant table). What I need to be able to do is
> > to a select using the keyid as the join criteria, but I only want to
> > return the first matching record and disregard any other matches. So
> > just to reconfirm, I want to do a select based on an address, join
> > based on the keyid and return the name of the first person that it
> > finds, disregarding any other occupants it finds. Any suggestions
> > would be greatly appreciated.
> > ex.
> > select table1.address, table2.name
> > from table1, table2
> > where address = '123 Main St'
> > and table1.keyid = table2.keyid
> >
> > What I am getting is
> > 123 Main St, Joe Blow
> > 123 Main St, John Q. Public ...
> >
> > but what I really want is whatever the first match is. I can't use
> > pl/sql in this case, has to be sql only. I'm hoping I'm just
> > overlooking something very simple, and BTW this is on oracle 8.0.5
Received on Wed Jul 03 2002 - 20:47:37 CDT

Original text of this message

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