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
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-----Original Message-----
From: pgsql-performance-owner@postgresql.org 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
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