Django OneToOneField deleting child doesn't set parents parameter as None? -

i have 2 models in django app

class product(models.modelfield):   name = ...  class discount(models.modelfield):   product_id = models.onetoonefield(product) 

basically, each product can have optional discount.now, assume have 1 product p discount d attached. want delete discount associated product p. so, use

p.discount.delete() 

while makes discount.objects.all() return [], p.discount still associated discount object.

how set attribute none?

p.discount = none 

changing in database not affect model instances in memory. in 1.8 can reload object db:

p.refresh_from_db() 

or before 1.8:

p = product.objects.get(pk=p.pk)