Abstract base class model that provides self-updating discriminators for fast multi-table inheritance.

models.py

from django.db import models


class DiscriminatedModel(models.Model):
    """
    An abstract base class model that provides self-updating discriminators for
    fast multi-table inheritance.

    """
    discriminator = models.CharField(max_length=255)

    def get_subclass(self):
        """
        Get concrete subclass throught reverse of implicit OneToOne link.

        """
        try:
            return getattr(self, self.discriminator)
        except:
            return self

    def save(self, *args, **kwargs):
        self.discriminator = self.__class__.__name__.lower()
        super(DiscriminatedModel, self).save(*args, **kwargs)

    class Meta:
        abstract = True