I am having a problem with left joins in Postgresql.(probably my
misunderstanding of left joins)
My first Query returns
70,000
select count(*)
from h
where h.tn 20
and h.tn 30
my left join
returns only 34,000
select count(*)
from h left join p using (r,pos)
where h.tn 20
and h.tn 30
Grant Morgan wrote:
I am having a problem with left joins in Postgresql.(probably my
misunderstanding of left joins)
My first Query returns
70,000
select count(*)
from h
where h.tn 20
and h.tn 30
my left join
returns only 34,000
select count(*)
from h left join p using (r,pos)
where
this helps
Nick
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
On Behalf Of Grant Morgan
Sent: 06 July 2005 11:02
To: pgsql-sql@postgresql.org
Subject: [SQL] left joins
I am having a problem with left joins in Postgresql.(probably my
misunderstanding of left joins)
My
Subject: [SQL] left joins
I am having a problem with left joins in Postgresql.(probably my
misunderstanding of left joins)
My first Query returns
70,000
select count(*)
from h
where h.tn 20
and h.tn 30
my left join
returns only 34,000
select count(*)
from h left join p using (r,pos)
where
Grant Morgan [EMAIL PROTECTED] writes:
select count(*)
from h left join p using (r,pos)
where h.tn 20
and h.tn 30
and p.r_order=1
since it is a left join I though I should get a number no smaller in
the left join than the original unjoined query. It seems to be acting
like an inner
Hi, all.
I've got a bit of a problem here. I have 4 tables - people, a, b, c (not
the original names).
For each person in the people table, they may or may not have a record in
a, may or may not have a record in b, and may or may not have a record in
c.
Handling the first table (a) is easy:
I've got a nasty query that joins a table onto itself like 22 times.
I'm wondering if there might be a better way to do this, and also how
I can left join every additional table on the first one. By this I
mean that if f1 matches my criteria and therefore isn't null, then
every other joined
I've got a select that pulls many values from the same table.
Basicaly for a given formid there can be many fields each one
depending on a definition. So form1 may be broken down as follows:
fieldid
1 firstname
2 lasname
3 postal code
Rather than sticking this data in
