Django Reverse Foreign Key FieldError

Question

I am trying to replicate Django's Each publisher, each with a count of books as a "num_books" attribute using the following models:

class Requests(models.Model):
    request_id      = models.AutoField(db_column='RequestId', primary_key=True)
    request_type    = models.ForeignKey('RequestTypes', db_column='RequestTypeId')
    ...
class RequestTypes(models.Model):
    request_type_id = models.CharField(db_column='RequestTypeId', primary_key=True)
    request_type_title           = models.CharField(db_column='Title')
    ...

From what I can tell, this should allow me to get a count of requests for each type using this:

Models.RequestTypes.objects.annotate(num_requests=Count('requests'))

But that just gives a FieldError , Cannot resolve keyword 'requests' into field.

Any ideas what I've missed?

Answer 1

Models.RequestTypes.objects.annotate(num_requests=Count('requests_set'))