bad address kep his from going to the list on my first try ... apologies to the
moderators.
-----Original Message-----
From: Gregory Williamson
Sent: Wed 9/5/2007 4:59 AM
To: JS Ubei; pgsql-performance@postgresql.org
Subject: RE: [PERFORM] optimize query with a maximum(date) extraction
In order to help others help you, you might provide the following:
table description (columns, types, indexes) (\d tablename from psql does nicely)
the same query run as "EXPLAIN ANALYZE <your query here>;"
Greg Williamson
Senior DBA
GlobeXplorer LLC, a DigitalGlobe company
Confidentiality Notice: This e-mail message, including any attachments, is for
the sole use of the intended recipient(s) and may contain confidential and
privileged information and must be protected in accordance with those
provisions. Any unauthorized review, use, disclosure or distribution is
prohibited. If you are not the intended recipient, please contact the sender by
reply e-mail and destroy all copies of the original message.
(My corporate masters made me say this.)
-----Original Message-----
From: [EMAIL PROTECTED] on behalf of JS Ubei
Sent: Wed 9/5/2007 3:53 AM
To: pgsql-performance@postgresql.org
Subject: [PERFORM] optimize query with a maximum(date) extraction
Hi all,
I need to improve a query like :
SELECT id, min(the_date), max(the_date) FROM my_table GROUP BY id;
Stupidly, I create a B-tree index on my_table(the_date), witch is logically not
used in my query, because it's not with a constant ? isn't it ?
I know that I can't create a function index with an aggregative function.
How I can do ?
thanks,
jsubei
_____________________________________________________________________________
Ne gardez plus qu'une seule adresse mail ! Copiez vos mails vers Yahoo! Mail
---------------------------(end of broadcast)---------------------------
TIP 5: don't forget to increase your free space map settings
