Question

I have separate apps with a foreign key from a model in one model (the UserProfile model) to another app I’ve created. When I try to syncdb I’m getting that the foreign key id is NULL even though I have a fixture for it in that app. Is there a way to specify the order in which YAML files are loaded?

Here’s what the app structure looks like –

profile/

# models.py
class UserProfile(models.Model):
    user = models.OneToOneField(User)
    school = models.ForeignKey(School)


def create_user_profile(sender, instance, created, **kwargs):
    if created:
        UserProfile.objects.create(user=instance)

post_save.connect(create_user_profile, sender=User)

# fixtures/initial_data.yaml
-   fields:
        username: admin
        password: ***password hash here***
        date_joined: 2012-02-01 01:00:00
        email: [e-mail]
        last_name: Last
        first_name: First
        groups: []
        is_active: true
        is_staff: true
        is_superuser: true
        last_login: 2012-02-01 01:01:00
        user_permissions: []
    model: auth.user
    pk: 1
-   fields:
        user: 1
        school: 1
    model: profile.UserProfile
    pk: 1

school/

# models.py
class School(models.Model):
    name = models.CharField(max_length=100)

# fixtures/initial_data.yaml
-   fields:
        name: "School"
    model: school.School
    pk: 1

And on syncdb I get:

IntegrityError: profile_userprofile.school_id may not be NULL

This must mean it’s saving the UserProfile model before the schools. So, I’m wondering if it’s at all possible to reorder the yaml files or somehow attribute the school to my UserProfile without allowing the school to be NULL.

In settings.py I’m loading school followed by profile in installed apps.

Answer 1

Right approach here is to use natural keys.

If you can’t use it, you can load fixtures manually, just rename them and load by manage.py loaddata in the order you need.