title: Filtering data by month from a date field Django
body: <p>I need to write a query that returns all objects in a month list. Month will be calculated from a date field i.e (2012-10-21 or 2011-04-14). When i am doing it for a single month its working fine
  <code>**Table.objects.filter(ad_date__month=month)**</code>. assume month = 05</p>
  
  <p>But when i am trying to do it in a list of months its not working.
  <code>**Table.objects.filter(ad_date__month__in=month_list)**</code>. assume month_list = [11, 03, 01, 10]</p>
  
  <p>I am getting this error:</p>
  
  <pre><code>"Join on field 'date' not permitted. Did you misspell 'month' for the lookup type?"
  </code></pre>
  
  <p>It seems Django considers it as a join operation.</p>
  
  <p>Please suggest, i am stuck in this problem from last 2 days.</p>