title: context.SaveChanges return 0 when updated without any change
body: <p>context.SaveChanges() returns 0 if I only hit the update button. If I don't change anything and just hit the update button, it returns 0. I am checking on the value which is returned by SaveChanges. Which are the conditions where SaveChanges returns 0. What are the return values indicate?</p>
  <p>Following is my code.</p>
  <pre><code>int returnValue = CS.SaveChanges();
                     return returnValue == 1 ? &quot;User profile has been updated successfully&quot; : &quot;Unable to update&quot;;
  </code></pre>