I created the index like this:
CREATE INDEX rcbee_idx
ON detail_summary
USING btree
(receipt, carrier_id, batchnum, encounternum, encounter_id);
Is this correct ?
How do I make a reverse opclass ?
----- Original Message -----
From: "Stephan Szabo" <sszabo@xxxxxxxxxxxxxxxxxxxxx>
To: "Josh Berkus" <josh@xxxxxxxxxxxx>
Cc: <pgsql-performance@xxxxxxxxxxxxxx>; <J@xxxxxxxxxxx>
Sent: Tuesday, January 17, 2006 5:40 PM
Subject: Re: [PERFORM] Multiple Order By Criteria
On Tue, 17 Jan 2006, Josh Berkus wrote:
J,
> I have an index built for each of these columns in my order by clause.
> This query takes an unacceptable amount of time to execute. Here are
> the
> results of the explain:
You need a single index which has all five columns, in order.
I think he'll also need a reverse opclass for the first column in the
index or for the others since he's doing desc, asc, asc, asc, asc.
---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
