On Fri, Nov 15, 2013 at 12:43 AM, Philippe Girolami <philippe.girol...@sensorly.com> wrote: > Ok so is there a way i can do something similar ? Would a function returning > rows and taking the extra predicate 'values' as parameters be as optimized as > the 'good' query in my first email ?
There is only one way I know of to do it (force a qual into a view wrapped into a subquery). It's tweaky, particularly with pre-9.3 LATERAL. The basic MO is to put the window function into SQL function in order to be able to force the qual into the inner query with a function parameter. Then, you make a view that cross products the possible arguments to the function and LATERALS them into the set returning function (it's possible, but difficult, to do it without lateral). As long as the 'arguments' expressed in the view are always specified in the query that hits the view performance should be good. If this sounds like something you'd like to tackle, maybe I can work up an example. merlin -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
