Menu
Let's say I have 2 models, one being the parent of another. How can I query all Places that aren't restaurants in Django? Place.objects.all() would include all restaurants right? I want to exclude the children from the results. Thank you!
class Place(models.Model):
name = models.CharField(max_length=50)
address = models.CharField(max_length=80)
class Restaurant(Place):
serves_hot_dogs = models.BooleanField()
serves_pizza = models.BooleanField()
397
The basics: Each model is a Python class that subclasses django.db.models.Model . Each attribute of the model represents a database field.
Nope. Django filters operate at the database level, generating SQL. To filter based on Python properties, you have to load the object into Python to evaluate the property--and at that point, you've already done all the work to load it.
The main Usage of a proxy model is to override the main functionality of existing Model. It is a type of model inheritance without creating a new table in Database. It always query on original model with overridden methods or managers.
An abstract model is a base class in which you define fields you want to include in all child models. Django doesn't create any database table for abstract models. A database table is created for each child model, including the fields inherited from the abstract class and the ones defined in the child model.
Filter on Django's automatically-created OneToOneField. If it IS NULL, this Place isn't a Restaurant.
non_restaurant_places = Place.objects.filter(restaurant__isnull=True)
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
