Ok thanks Massimo. On Fri, Jan 20, 2012 at 5:09 PM, Massimo Di Pierro < [email protected]> wrote:
> yes. :-) > > On Jan 20, 5:48 pm, Bruce Wade <[email protected]> wrote: > > Would this be the best approach: > > todays_ids = set(used_ad_ids) > > unseen_ads_query = self.db(~self.db.ads.id.belongs(todays_ids)) > > unseen_ads_query = unseen_ads_query(self.db.ads.points >= 0) > > unseen_ads_query = unseen_ads_query(self.db.ads.viewable == True) > > unseen_ads_query = unseen_ads_query(self.db.ads.accepted == True) > > *unseen_ads = unseen_ads_query.select(orderby='<random>', > > limitby=(0,5))* > > > > > > > > > > > > > > > > > > > > On Fri, Jan 20, 2012 at 3:34 PM, Bruce Wade <[email protected]> > wrote: > > > Hi, > > > > > I have selected a list of objects from the database, which is working. > Now > > > I would like to select 5 random rows from the list and ideally only > hit the > > > database once to get them 5 random rows. > > > > > todays_ids = set(used_ad_ids) > > > unseen_ads_query = self.db(~self.db.ads.id.belongs(todays_ids)) > > > unseen_ads_query = unseen_ads_query(self.db.ads.points >= 0) > > > unseen_ads_query = unseen_ads_query(self.db.ads.viewable == > True) > > > unseen_ads_query = unseen_ads_query(self.db.ads.accepted == > True) > > > unseen_ads = unseen_ads_query.select() > > > > > # now pull 5 random rows out of the returned rows, each time > this > > > method is called the random 5 should always be different from the last > call. > > > # Can this be done before the last select() statement and > allow to > > > use limit(5) so the database isn't hit so hard if there were 1,000,000 > > > results in the select() and I only need 5 random out of the 1,000,000 > > > > > return unseen_ads > > > > > Also please let me know if their is a more efficient way to do the > above > > > query. > > > > > -- > > > -- > > > Regards, > > > Bruce Wade > > >http://ca.linkedin.com/in/brucelwade > > >http://www.wadecybertech.com > > >http://www.warplydesigned.com > > >http://www.fitnessfriendsfinder.com > > > > -- > > -- > > Regards, > > Bruce Wadehttp:// > ca.linkedin.com/in/brucelwadehttp://www.wadecybertech.comhttp://www.warplydesigned.comhttp://www.fitnessfriendsfinder.com > -- -- Regards, Bruce Wade http://ca.linkedin.com/in/brucelwade http://www.wadecybertech.com http://www.warplydesigned.com http://www.fitnessfriendsfinder.com
