JTree & database: ID column ?

From: maRIO5 (mario_zupan_at_inet.hr)
Date: 12/23/03 

Date: Tue, 23 Dec 2003 00:10:28 +0100

Idevelop the JTree which create,update and delete nodes
from database and for it I use ID1 column which is unique
and ID2 which is pointer on the parent node.
My ID1 is look like this:
0.0
0.1
0.1.0
0.2
0.2.0
0.2.1
0.2.1.0
0.2.1.0.0
0.2.1.0.1
and every number in a code represents the place in a parent node.

and my ID2 is a pointer on a parent node.
0
0
0.1
0
0.2
0.2
0.2.1
0.2.1.0
0.2.1.0

Does it too complicated and doi you have a simplier solution?
I have problems with the column sorting because it must be a string
(because this "." is a separator)