title: Thinking Sphinx, Rails, :has_many :through => ... has
body: <p>Model: Product</p>
  
  <pre><code>has-many product-categories, :through =&gt; ...
  </code></pre>
  
  <p>Question 1) How do I index a many to many association with thinking sphinx</p>
  
  <p>Must I use has?</p>
  
  <p>Questions 2) How is this searched in the controller</p>
  
  <p>ex. Product.search params[:search-params], :conditions => {some_conditions}</p>