Question

0

154

Views

Django - how to save method apply only on new data

How do I manipulate this method to be applied only on new entries and does not have a previous entry.

When in admin, I will add an record, this method is applied correctly. but when I edit the same record, this method is applied again.

def save(self):
    p = Product.objects.last()
    if p:
        self.productnumber = 1000 + p.id
    else:
        self.productnumber = 1000
    super(Product, self).save()

about 4 years ago · Santiago Trujillo

2 answers

Answer question

0

Two ways are there.

1. post_save

@receiver(post_save, sender= Product)
def my_callback(sender, instance, created, *args, **kwargs):
    if created:
        #new
    else:
        #update

2. check primary key exists

def save(self):
    if self.pk: #or id
        #update
    else:
        #new

about 4 years ago · Santiago Trujillo Report

0

Answer question

Find remote jobs

Accepted Answer · 2022-06-14T16:52:45.841Z

If you want to execute some code in the save() method, only for non-existing items you should check if a primary key exists.

def save(self):
    if self.pk is None:
        # Code for new objects
    else:
        # Code for existing objects

0

154

Django - how to save method apply only on new data

2 answers

0

0

Find remote jobs

Andres GPT