data.rst

Data fixtures

Export/dump data to use as a fixture:

python manage.py dumpdata --format=yaml --natural app.model >data.yaml

Load it again:

python manage.py loaddata data.yaml

Natural keys

https://docs.djangoproject.com/en/dev/topics/serialization/#natural-keys

from django.db import models

class PersonManager(models.Manager):
    def get_by_natural_key(self, first_name, last_name):
        return self.get(first_name=first_name, last_name=last_name)

class Person(models.Model):
    objects = PersonManager()
    ...

    def natural_key(self):
        return (self.first_name, self.last_name)

    class Meta:
        unique_together = (('first_name', 'last_name'),)

Dependencies

If part of the natural key is a reference to another model, then that model needs to be deserialized first:

class Book(models.Model):
    name = models.CharField(max_length=100)
    author = models.ForeignKey(Person)

    def natural_key(self):
        return (self.name,) + self.author.natural_key()
    natural_key.dependencies = ['example_app.person']