On 10/07/2009, Devel63 <danstic...@gmail.com> wrote:
>
> The best way is to assign a one-up counter to each record as you
> create it, then call random.randint(1,max_counter) to determine the
> desired record.
>
> To retrieve multiple random entities in a query, do a filter('IN ',
> [my random nums]).
doent work that well once records start getting deleted (get the same
issue, non uniform distribution)
nor does it work if you filtering at the same time :(
>
> Note that behind the scenes this generates multiple queries, so you're
> not saving much time.
>
>
> On Jul 10, 7:34 am, Wooble <geoffsp...@gmail.com> wrote:
> > Highly non-optimal solution: have a cron job assign new random numbers
> > to your entities often enough to simulate randomness. Even just re-
> > assigning numbers to entities that have been previously selected might
> > work. This involves a lot more CPU as you'd be doing writes, but
> > shifts the work from request time to a background process so your
> > users don't see the added latency for doing N queries.
> >
> > Another possible solution would be to fetch keys only for X*N entities
> > (where greater X's produce more apparent randomness) then choose N of
> > those keys to actually fetch entities.
> >
> > On Jul 9, 12:33 pm, aloo <aleem.maw...@gmail.com> wrote:
> >
> > > Hi all,
> >
> > > I'm trying to write a GQL query that returns N random records of a
> > > specific kind. My current implementation works but requires N calls to
> > > the datastore. I'd like to make it 1 call to the datastore if
> > > possible.
> >
> > > I currently assign a random number to every kind that I put into the
> > > datastore. When I query for a random record I generate another random
> > > number and query for records > rand ORDER BY asc LIMIT 1.
> >
> > > This works, however, it only returns 1 record so I need to do N
> > > queries. Any ideas on how to make this one query? Thanks.
> >
>
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