Sampling with joins using Django models

I have a method in one of my models that right now fetches every link, and then does a random sample. Is it possible to make some form of join combined with a random selection using Django models? The current method seems like a great way to waste grind the application to a halt when the data grows. :)

class Link(models.Model):
    link = models.URLField()
    in_list = models.ForeignKey( 'linkrotator.LinkList',
                                 related_name = 'links' )


class LinkList(models.Model):
    in_list = models.ForeignKey('linkrotator.LinkListList',
                            blank = True,
                            null = True,
                            on_delete=models.SET_NULL,
                            related_name = 'lists')

class LinkListList(models.Model):
    number_of_links = models.IntegerField()
    def get_links(self):
        links = []
        for list in self.lists.all():
            links.extend( list.links.all() )
        if len( links ) <开发者_C百科;= self.number_of_links:
            return links
        return random.sample( links, self.number_of_links )

You can get a bunch of random links like this:

links = self.lists.all().order_by('?')[self.number_of_links]

But... that doesn't filter on the lists you want. You might be able to do something like this to get that: filter(list_set__id__in=...)

I thinks it's useful for Getting a random row from a relational database