mysql> create table treeNodes-> (-> id int primary key,-> nodename varchar(20),-> pid int-> );Query OK, 0 rows affected (0.09 sec)mysql> select * from treenodes;+----+----------+------+| id | nodename | pid |+----+----------+------+|

1 | A | 0 ||

2 | B | 1 ||

3 | C | 1 ||

4 | D | 2 ||

5 | E | 2 ||

6 | F | 3 ||

7 | G | 6 ||

8 | H | 0 ||

9 | I | 8 ||

10 | J | 8 ||

11 | K | 8 ||

12 | L | 9 ||

13 | M | 9 ||

14 | N | 12 ||

15 | O | 12 ||

16 | P | 15 ||

17 | Q | 15 |+----+----------+------+17 rows in set (0.00 sec)