public function setAttribute($key, $val)
    {
        try {
            return $this->_stmt->setAttribute($key, $val);
        } catch (PDOException $e) {
            // require_once 'Zend/Db/Statement/Exception.php';
            throw new Zend_Db_Statement_Exception($e->getMessage(), $e->getCode(), $e);
        }
    }