title: How to update model B when modification of model A happens?
body: <p>I'm developing with django an application for the management of the company budget.
  I noticed that with django to be able to modify the data contained in my db I always have to go through a required view. But, once I have entered data through a form, I would like to make changes to the dataset. Is it possible?</p>
  
  <p>I'll give you an example:</p>
  
  <p>through my form I collect the data of the monthly collections per business unit:</p>
  
  <pre><code>                  | ____ Jan ____ | ___ Feb _____ |
  
  Business unit_1 | ____ 100 ___ | _____ 100 ____ |
  
  Business unit_2 | ____ 100 ____ | ____ 100 ____ |
  </code></pre>
  
  <p>I'd like to populate another model at once with totals per month from the data shown above:</p>
  
  <pre><code>      | ____ Jan ____ | ___ Feb _____ |
  total | ____ 200 ____ | ____ 200 ____ |
  </code></pre>
  
  <p>And I want that, if I delete a row in business unit, automatically the total is udpdated. </p>
  
  <p>Do you think I can do it directly in the view and so utilziing only django? if yes how? or do you recommend another way ?</p>