How do I change the choices in a Django model?

Question

I have a Django model that uses the choices attribute.

COLOR_CHOICES = (
    ('R', 'Red'),
    ('B', 'Blue'),
)
class Toy(models.Model):
    color = models.CharField(max_length=1, choices=COLOR_CHOICES)

My code is in production and now I'd like to add additional choices.

COLOR_CHOICES = (
        ('R', 'Red'),
        ('B', 'Blue'),
        ('G', 'Green'),
 )

How do I go about doing this? Does Django use Database constraints to enforce choices? Do I need to do a Database migration (I'm using South)? Or does Django just enforce the choices restriction in Python code and all I have to do is change the code and restart?

Thanks!

Answer 1

Django doesn't enforce choices on a database level, it only uses them for the presentation of the widgets and in validation. If you want them a bit more 'dynamic', for example to have different ones on different servers you could define them via settings.py:

from django.conf import settings

COLOR_CHOICES = getattr(settings, 'COLOR_CHOICES',(
        ('R', 'Red'),
        ('B', 'Blue'),
        ('G', 'Green'),
 ))

Then you could define different choices in your settings.py (no need for any database migration!).