[Answered ]-Django-haystack with sharded database

Well this of course depends on your app regarding User.

If you have 6 User Models like User1, User2, ... User6 you could do by writing an own manager for model User, which then will return all Users on self.get_model().objects.all() and also could manage your sharded Database.

To know what you like to do and how you did so far it would not to have more information about your current setup