title: is it correct to unset the session variable for a particular index as the vay whole session is made unset in PHP?
body: <p>is it correct to unset the session variable for a particular index as the vay whole session is made unset in PHP?</p>
  
  <p>I know this works: <code>unset($_SESSION['bannersize'])</code></p>
  
  <p>But does this works ? : <code>unset($_SESSION['bannersize'][3])</code></p>
  
  <p>or is there any other way to unset any particular desired index of the session <strong>and then again rearrange the values inside it to remove the empty index</strong>..?</p>