Re: Multiple Order By Criteria - Mailing list pgsql-performance

On Tue, 17 Jan 2006 J@Planeti.Biz wrote:

> 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 ?

That would work if you were asking for all the columns ascending or
descending, but we don't currently use it for mixed orders.

> How do I make a reverse opclass ?

There's some information at the following:
http://archives.postgresql.org/pgsql-novice/2005-10/msg00254.php
http://archives.postgresql.org/pgsql-general/2005-01/msg00121.php
http://archives.postgresql.org/pgsql-general/2004-06/msg00565.php