title: Django forms which fields are required as "bound" fields to validate
body: <p>Per this question: <a href="https://stackoverflow.com/questions/7920128/difference-between-django-form-initial-and-bound-data">Difference between Django Form &#39;initial&#39; and &#39;bound data&#39;?</a> :</p>
  
  <blockquote>
    <p>Here's the key part from the django docs on bound and unbound forms.</p>
    
    <p>If it’s bound to a set of data, it’s capable of validating that data and rendering the form as HTML with the data displayed in the
    HTML.</p>
    
    <p>If it’s unbound, it cannot do validation (because there’s no data to validate!), but it can still render the blank form as HTML.</p>
  </blockquote>
  
  <p>My question is:
  Is there an easy way to know <em>which</em> fields <em>need</em> to be bound in order to validate?</p>
  
  <p>We have a multi-inheritance ModelForm nightmare and it's really tough to figure out which what are the minimum required fields to "bind". </p>
  
  <p>In this case I've tried matching my <code>form.data</code> to  <code>vars(form.fields)</code>, but this is not enough, it's just ongoing potluck tracking back through the models and adding more and more to the <code>form.data</code> in an ad-hoc way.</p>
  
  <p>Is there some cardinal list somewhere of the minimum requirements of bindable fields?</p>