From: | Ben <bench(at)silentmedia(dot)com> |
---|---|
To: | pgsql-general(at)postgresql(dot)org |
Subject: | Apparently I don't understand full outer joins.... |
Date: | 2005-01-25 20:29:07 |
Message-ID: | Pine.LNX.4.44.0501251226110.9786-100000@localhost.localdomain |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
I run this:
select
coalesce(a.n,0) as a,
coalesce(b.n,0) as b,
coalesce(a.s,b.s) as s
from
( select 1 as n, 0 as s) a full outer join
( select 2 as n, 1 as s) b
on
a.s = b.s
... and get this:
a | b | s
---+---+---
1 | 0 | 0
0 | 2 | 1
(2 rows)
Perfect! Now, I try to extend my understanding to 3 subselects:
select
coalesce(a.n,0) as a,
coalesce(b.n,0) as b,
coalesce(c.n,0) as c,
coalesce(a.s,b.s,c.s) as s
from
( select 1 as n, 0 as s) a full outer join
( select 1 as n, 1 as s) b full outer join
( select 2 as n, 2 as s) c
on
a.s = b.s and
b.s = c.s
.... and get a syntax error at the end of my query. Apparently what I'm
trying to do doesn't make sense?
Oh, this is on version 7.4, if that makes a difference.
---
Ben Chobot
Senior Technical Specialist, Washington Mutual
206-461-4005
From | Date | Subject | |
---|---|---|---|
Next Message | Thomas F.O'Connell | 2005-01-25 20:49:30 | Re: Apparently I don't understand full outer joins.... |
Previous Message | Martijn van Oosterhout | 2005-01-25 20:26:39 | Re: Extended unit |