title: django using cached database query problem
body: <p>I have django application witch save traffic logs .
  the problem is when we refresh page doesnt show new logs its like query set cached some where.
  I made a manager to return last n log.</p>
  
  <p>this is my code</p>
  
  <pre><code>from django.db.models import Manager 
  
  class LogMannager(Manager):
      def _last(self,num,server=None,camera=None):
          if  camera:
              return self.get_queryset().filter(camera=camera).order_by('-id')[:num]
          elif server:
              return self.get_queryset().filter(server=server).order_by('-id')[:num]
          else:
              ret = self.get_queryset().all().order_by('-id')[:num]
              print(ret)
              return ret
  </code></pre>
  
  <p>the server is in production and using uwsgi </p>
  
  <p>update:</p>
  
  <p>this is where am i using :</p>
  
  <pre><code>class MainKioskView(MainMixin, generic.TemplateView):
      template_name = 'monitoring/main_kiosk.html'
      log = Log.objects._last(30)
      all_server = Server.objects.all()
      servers = [[server, Log.objects.filter(server=server).last(), ActiveCamera.objects.filter(server=server)] for server
                 in all_server]
      extra_context = {'logs': log, 'servers': servers}
  </code></pre>