title: What does inverse_of do? What SQL does it generate?
body: <p>I'm trying to get my head around <code>inverse_of</code> and I do not get it. </p>
  
  <p>What does the generated sql look like, if any?</p>
  
  <p>Does the <code>inverse_of</code> option exhibit the same behavior if used with <code>:has_many</code>, <code>:belongs_to</code>, and <code>:has_many_and_belongs_to</code>?</p>
  
  <p>Sorry if this is such a basic question.</p>
  
  <p>I saw this example:</p>
  
  <pre><code>class Player &lt; ActiveRecord::Base
    has_many :cards, :inverse_of =&gt; :player
  end
  
  class Card &lt; ActiveRecord::Base
    belongs_to :player, :inverse_of =&gt; :cards
  end
  </code></pre>