> You are aware that FB can combine single-column indexes in most (all?)
> cases? You may need one ascending and one descending index per column.
> For ten columns that would result in twenty indexes. So, what are the
> other ten for?

yes i know, and what you do with order by ? when you do a query, with index to choose to use in the plan ? the index on the order by or the index on the filter? to know that you must know BEFORE to do the query the amount of row the filter will return to you !

the only way i found is to use index on both order by + filter
for exemple
where id_agent=xxx and id_location=yyy and price=wwww order by id_agent desc, id_location desc, nb_room desc
use plan with index idagent_idlocation_nbroom + (eventually) index on price

stephane