Re: Indexes with descending date columns

On Thu, Mar 23, 2006 at 01:09:49PM +0200, Theo Kramer wrote:
> ii If no to i, is it feasible to extend PostgreSQL to allow traversing
> an index in column descending and column ascending order - assuming
> an order by on more than one column with column order not
> in the same direction and indexes existing? ... if that makes sense.

Yes.

stats=# explain select * from email_contrib order by project_id desc, id desc, date desc limit 10;
QUERY PLAN
------------------------------------------------------------------------------------------------------------------------
Limit (cost=0.00..31.76 rows=10 width=24)
-> Index Scan Backward using email_contrib_pkey on email_contrib (cost=0.00..427716532.18 rows=134656656 width=24)
(2 rows)

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Jim C. Nasby, Sr. Engineering Consultant jnasby(at)pervasive(dot)com
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