title: PDO MySQL Connection close - unset vs null
body: <p>I've read in PDO manual that to close connection you should use the following:</p>
  
  <pre><code>$connection = null;
  </code></pre>
  
  <p>However, Some people suggested that since PHP 5.3 has a new GC, the following should be used:</p>
  
  <pre><code>unset($connection);
  </code></pre>
  
  <p>I need to know once and for all, which one is preferred, or are they the same?</p>