Django model filter with field_set, keep as queryset -

i have filter list method works, , can used, when try make , order_by on list, in can't done.

how can , keep queryset make order_by after filter applied,

i don't know of there better way work field_set's ?

models:

class case(models.model):     user = models.foreignkey(user)     ....  class share(models.model):     case = models.foreignkey(case)     ....  class field(models.model):     case = models.foreignkey(case)     field = models.foreignkey(defaultfield)     .... 

-

object_list = field.objects.all()  l = [f f in object_list if f.case.share_set.filter(user=request.user).count()] 

this inefficient thing in case. should try , filtering in database as possible. query means db has send field rows django, instantiate them, throw away ones don't match. instead should query ones want:

object_list = field.objects.filter(case__share__user=request.user) 

now, being more efficient, have queryset on can call order_by.