Django self-referential foreign key

python django django-orm
sfendell picture sfendell · Mar 8, 2013 · Viewed 65.2k times · Source

I'm kind of new to webapps and database stuff in general so this might be a dumb question. I want to make a model ("CategoryModel") with a field that points to the primary id of another instance of the model (its parent).

class CategoryModel(models.Model):
    parent = models.ForeignKey(CategoryModel)

How do I do this? Thanks!

Answer

Jared Forsyth picture Jared Forsyth · Mar 8, 2013

You can pass in the name of a model as a string to ForeignKey and it will do the right thing.

So:

parent = models.ForeignKey("CategoryModel")

Or you can use the string "self"

parent = models.ForeignKey("self")

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