class Sum(expression, output_field=None, **extra) [source] Computes the sum of all values

lookup_name The name of the lookup, used for identifying it on parsing query expressions. It cannot contain the string "__"

Options.app_label If a model is defined outside of an application in INSTALLED_APPS, it must declare which app

Options.required_db_features New in Django 1.9. List

template A class attribute, as a format string, that describes the SQL that is generated for this aggregate. Defaults to '%(function)s(

ForeignKey.db_constraint Controls whether or not a constraint should be created in the database for this foreign key. The default

formfield(form_class=None, choices_form_class=None, **kwargs) [source] Returns the default

pre_save(model_instance, add) [source] Method called prior to get_db_prep_save()

rel_db_type(connection) [source] New in Django

Model.get_absolute_url() Define a get_absolute_url() method to tell Django how to calculate the canonical URL for