From: | Mark Wimer <mwimer(at)usgs(dot)gov> |
---|---|
To: | Ashish Karalkar <ashish_postgre(at)yahoo(dot)co(dot)in> |
Cc: | ashish(dot)karalkar(at)netcore(dot)co(dot)in, pgsql-novice(at)postgresql(dot)org |
Subject: | Re: SQL Query |
Date: | 2007-12-13 17:23:39 |
Message-ID: | OF27C227F3.63C28F73-ON852573B0.005F68AC-852573B0.005F8CEF@usgs.gov |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general pgsql-novice |
See if this works; the max aggregate in the subquery could be just about
any function, since it's only going to join to one row.
select max(m1.output_date), m1.parent_id, max(m2.output_id) as
latest_output
from my_table M1 inner join (select output_date, output_id, parent_ID from
my_table) as M2
on m1.output_date = m2.output_date and m1.parent_ID = m2.parent_ID
Where M1.output_date < now()
Group by m1.parent_id
-- Mark
Ashish Karalkar <ashish_postgre(at)yahoo(dot)co(dot)in>
Sent by: pgsql-novice-owner(at)postgresql(dot)org
12/13/2007 04:47 AM
To
pgsql-novice(at)postgresql(dot)org, ashish(dot)karalkar(at)netcore(dot)co(dot)in
cc
Subject
[NOVICE] SQL Query
Hello List member,
I have a table which ha sfollowing structure
my_table:
(
output_id serial priimary key,
parent_id int,
output_date timesatmp
)
parent_table:
(parent_id int,
parent desc
)
the my_table contains data for previous as well as future output dates.
for single parent there may be multiple rows.
I want to retrieve all the output_id which are having latest output_date
but less than now() (no future output_dates) group by parent_id
Thanks in advance
With Regards
Ashish...
Chat on a cool, new interface. No download required. Click here.
From | Date | Subject | |
---|---|---|---|
Next Message | Reg Me Please | 2007-12-13 17:36:43 | COPY speedup |
Previous Message | Scott Marlowe | 2007-12-13 17:03:18 | Re: Need to find out which process is hitting hda |
From | Date | Subject | |
---|---|---|---|
Next Message | A. Kretschmer | 2007-12-13 20:24:17 | Re: remote user |
Previous Message | Tom Lane | 2007-12-13 16:37:30 | Re: Is now() atomic? |