On Wed, 19 Apr 2017, Mike Dewhirst wrote:
You probably need a single FK plus a meta option of unique_together https://docs.djangoproject.com/en/1.8/ref/models/options/#unique-together
Use the model's clean() method ... https://docs.djangoproject.com/en/1.8/ref/models/instances/#django.db.models.Model.clean
Mike, I'll read how to use these. Thanks, Rich
