thx, take a random seed form the session and shuffle data is a good idea looks like slow because of amount od data, but I can save the random numbers for each row in the database and make 2 selects, one > then random(seed) and join it with the other, <= random(seed)
On 22. Sep., 14:31 h., Tim Chase <[email protected]> wrote: > > I need ordering units in random order, but keep the order for browsing > > per pages and also keep the order for changeable filtering options, > > like startswith and contains. What are the best solutions? There is > > huge amount of units and I read the order by RANDOM() or especialy > > MySQL RAND() is very slow. Have you any experience/solutions? > > My first thought would be to bring back the results in a > predictable order that can't be changed. That will ensure that > they don't change over time. You can then use the "random" > module's seed/shuffle calls to shuffle the given instance. You > merely have to set the seed in your session information: > > import random > ... > data = list(MyObject.objects.filter(...).order('predictable')) > seed = request.GET.get('seed', random.randint(0, 10000)) > r = random.Random() > r.seed(seed) > r.shuffle(data) > do_stuff(data, seed) # pass the seed to the template > # paginator so it can be passed in on the next page > > This works because if you take data in a known-order sequence, > set the random-generator's seed, and then shuffle the data based > on that sed, you should get the same pseudo-random order each > time you use the same seed. So the trick is to choose a random > seed once per "browsing". > > -tim --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
