The shop example (ch 8), the orders model has no items #24

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1. hmbarotov commented on Jul 22, 2024

   

   hmbarotov

   on Jul 22, 2024

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   Hi,

   This is a ForeignKey field. self.items.all is referring to its child model OrderItem. There is an OrderItem model beneath:

   class OrderItem(models.Model):
       order = models.ForeignKey(Order, related_name="items" , on_delete=models.CASCADE)
       product = models.ForeignKey(
           Product, related_name="order_items", on_delete=models.CASCADE
       )
       price = models.DecimalField(max_digits=10, decimal_places=2)
       quantity = models.PositiveIntegerField(default=1)
   
       def __str__(self):
           return str(self.id)
   
       def get_cost(self):
           return self.price * self.quantity
   

   The OrderItem is the child of the model Order. In Django, the default way is to access the child model this way:

   self.orderitem_set.all()
   

   As the related_name is set to items, we can access the child model using the given syntax.

   class OrderItem(models.Model):
       order = models.ForeignKey(Order, related_name="items" , on_delete=models.CASCADE)