public function commit()
 {
     if (!$this->transaction) {
         return;
     }
     parent::commit();
     $allCommands = array();
     $allParams = array();
     $allOptions = array('transaction' => true, 'action' => 'batch');
     foreach ($this->buffer as $i => $buffer) {
         list($sql, $params, $options) = $buffer;
         $allCommands[$i] = $sql;
         $allParams[$i] = $params;
         $allOptions[$i] = $options;
     }
     $this->send($allCommands, $allParams, $allOptions);
     $this->buffer = array();
 }