I need to remember to keep things simple...
Works fine, thanks.
Fred
On Jun 1, 2005, at 5:20 PM, Jim Buttafuoco wrote:
how about (untested)
select *
from
(
SELECT DISTINCT ON (linkid) *
FROM all_links
WHERE uid='2' AND DATE_TRUNC('day',read_date) = DATE_TRUNC
('day',TIMESTAMP '2005-06-01')
ORDER BY linkid
) A
ORDER BY read_date DESC limit 100
---------- Original Message -----------
From: FC <lne-1mc8@xxxxxxxxxxx>
To: pgsql-general@xxxxxxxxxxxxxx
Sent: Wed, 1 Jun 2005 16:40:48 +0200
Subject: SQL question.
Hello SQL Aces !
I want to do a select on a table distinct on linkid and sorted by
date. I have try this
SELECT DISTINCT ON (linkid) * FROM all_links
WHERE uid='2' AND DATE_TRUNC('day',read_date) = DATE_TRUNC('day',
TIMESTAMP '2005-06-01') ORDER BY linkid, read_date;
With this request "works" but the raws are sorted as I want. To have
the rows sorted by date I have done this using a temporary table and
that works exactly as I want.
CREATE LOCAL TEMP TABLE temp_links WITHOUT OIDS AS
SELECT DISTINCT ON (linkid) * FROM all_links
WHERE uid='2' AND DATE_TRUNC('day',read_date) = DATE_TRUNC('day',
TIMESTAMP '2005-06-01') ORDER BY linkid;
SELECT * from temp_links ORDER BY read_date DESC limit 100
My question is... How can I do the same thing in the more efficient
way and without using a temporary table. Since I am using PHP and the
table is not deleted at the end of the program because PHP keeps the
connection to the database open.
Thanks for any suggestions.
Fred
---------------------------(end of
broadcast)---------------------------
TIP 2: you can get off all lists at once with the unregister command
(send "unregister YourEmailAddressHere" to
majordomo@xxxxxxxxxxxxxx)
------- End of Original Message -------
---------------------------(end of broadcast)---------------------------
TIP 3: if posting/reading through Usenet, please send an appropriate
subscribe-nomail command to majordomo@xxxxxxxxxxxxxx so that your
message can get through to the mailing list cleanly
