On Fri, 2006-03-24 at 12:21, Jim C. Nasby wrote: > 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) Not quite what I mean - redo the above as follows and then see what explain returns explain select * from email_contrib order by project_id, id, date desc limit 10; -- Regards Theo
