public function dump() : string
    {
        $html  = '<p><i>You have made ' . self::$numQueries . ' database queries.</i></p><pre>';
        
        foreach (self::$queries as $key => $val) {
            $params = empty(self::$params[$key])
                ? null
                : htmlentities(print_r(self::$params[$key], 1), null, 'UTF-8') . '<br/><br/>';
            $html .= htmlentities($val, null, 'UTF-8') . '<br/><br/>' . $params;
        }
        
        return $html . '</pre>';
    }