title: Error when preparing a multiple insert query
body: <pre><code>// BUILD VALUES
  $count = count($matches);
  for($i = 0; $i &lt; $count; ++$i) {
      $values[] = '(?)';
  }
  // INSERT INTO DATABASE
  $q = $this-&gt;dbc-&gt;prepare(&quot;INSERT INTO hashes (hash) VALUES &quot; . implode(', ', $values) . &quot; ON DUPLICATE KEY UPDATE hash = hash&quot;);
  $q-&gt;execute($matches);
  </code></pre>
  <p>The code above fails with the following error</p>
  <p><strong>SQLSTATE[HY093]: Invalid parameter number: parameter was not defined</strong></p>
  <p>Although when <code>count($matches) == count($values)</code> just before execute is called?</p>
  <p>What is going on here?</p>