public function _fetchBound($row)
    {
        foreach ($row as $key => $value) {
            // bindColumn() takes 1-based integer positions
            // but fetch() returns 0-based integer indexes
            if (is_int($key)) {
                $key++;
            }
            // set results only to variables that were bound previously
            if (isset($this->_bindColumn[$key])) {
                $this->_bindColumn[$key] = $value;
            }
        }
        return true;
    }