trees in postgres

Hello All,

I have just searched the pgsql-sql mail archive for the tree keyword.
I have found several interesting articles in the field of graphs:
http://www.postgresql.org/mhonarc/pgsql-sql/1999-01/msg00065.html
http://www.postgresql.org/mhonarc/pgsql-sql/1999-01/msg00107.html
http://www.postgresql.org/mhonarc/pgsql-sql/1999-01/msg00081.html

>From this articles is more or less clear what one can do with one big
graph.
My situation is a little bit differs. I want to write down molecules
like graphs (it is realy common because of the connectivity matrix) to
have the opportunity to search a substructure (subgraph).
The problem is that I have more than one molecule. Is it a good or bad
idea to create a type like this

id
atom_type
charge
connected_to_id(10 times)
bond_type(10 times)

and create an other type as an array of the first type? After this I can
write down a molecule in one row of my table.

Has anyone some idea or experience in this field?

Laszlo Molnar
Gedeon Richter Ltd.
Hungary