How do I use the clean method in Django models?

How do I use the clean method in Django models?

The clean method in Django models is used to validate model fields before saving. You can override it to add custom validation logic.

Can you give me an example of how to implement it?

Sure! Here's a simple example:

from django.db import models

class MyModel(models.Model):
    name = models.CharField(max_length=100)
    age = models.IntegerField()

    def clean(self):
        if self.age < 0:
            raise ValidationError('Age cannot be negative.')

What happens if the validation fails?

If the validation fails, a ValidationError will be raised, and the model instance won't be saved to the database.

Can I use clean methods for multiple fields?

Yes, you can validate multiple fields in the clean method by accessing them using self.field_name and adding your custom logic.