Create a sub table row from existing parent.

[obayemi]

Hello,

Would it be possible to extend an already saved polymorphic model?

class A(PolymorphicModel)
    pass

class B(A):
    pass

would it be possible to turn an instance of A to an instance of B ?
like some sort of B(A=A()).
(I guess it would be technically possible since inheritance only store a pointer to the base class?)

[vdboor]

This it's possible to "upgrade" a polymorphic model, but sadly this still needs some manual action.

Something like this will work:

a = A.objects.get(..)
b = B(pk=a.pk)
b.save_base(raw=True, force_insert=True)
b.refresh_from_db()
b.save()  # saves polymorphic_ctype

However, it would be really useful to provide an API for this.