获取树评论

Can't get normal tree of comments from database:

Function in model to get data (I use Codeigniter)

public function get_test()
    {
        $query = $this->db->get('test');
        $dataset = $query->result_array();
        foreach($dataset as &$row) {
            if (!$row['parent_id']) {
                $tree[$row['id']] = &$row;
            } else {
                $tree[$row['parent_id']]['children'][$row['id']] = &$row;

            }
        }
        return $tree;
    }

<? echo '<pre>';
    print_r($test);
    echo '</pre>'; ?>

And this is what I get:

Array
(
    [1] => Array
        (
            [id] => 1
            [parent_id] => 0
            [name] => Маша
            [comment] => Привет всем
            [children] => Array
                (
                    [2] => Array
                        (
                            [id] => 2
                            [parent_id] => 1
                            [name] => Саша
                            [comment] => И тебе првиет
                        )

                )

        )

    [3] => Array
        (
            [id] => 3
            [parent_id] => 0
            [name] => Даша
            [comment] => Ауау
            [children] => Array
                (
                    [4] => Array
                        (
                            [id] => 4
                            [parent_id] => 3
                            [name] => Паша
                            [comment] => Читай
                        )

                )

        )

    [2] => Array
        (
            [children] => Array
                (
                    [5] => Array
                        (
                            [id] => 5
                            [parent_id] => 2
                            [name] => Петя
                            [comment] => Еще привет
                        )

                )

        )

)

The last array It must be a response to a comment in the first array....What is the problem? I can't find a mistake.

Check again your database maybe by using phpmyadmin because as i saw from the printed array the comment with [id] => 5 has [parent_id] => 2. If you want to display it as child of the comment with [id] => 1 you have to give him the [parent_id] => 1