looking for some suggestions

Hi,

I am looking for some suggestions on my test example.

I have two tables: one for persons and the other for dependents table,
which is shown below. I would like to concatenate all children of the
same parents in a single string such as:

 Children
-----------------
 Kidc One
 Kidf Two, Kidg Two

Can anyone help me how to do that from the following tables?

I have installed PostgreSQL 8.1.3.

The tables and their records are given below.

create table persons
(
    person_id      serial                        ,
    fname          varchar(32)                   ,
    CONSTRAINT     person_pk PRIMARY KEY(person_id)
);

create table dependents
(
    parent_id     integer               not null,
    child_id      integer               not null,
    CONSTRAINT    dependents_pk PRIMARY KEY(parent_id, child_id)
);


insert into persons(fname) values('Dada One');
insert into persons(fname) values('Momb One');
insert into persons(fname) values('Kidc One');

insert into persons(fname) values('Dadd Two');
insert into persons(fname) values('Mome Two');
insert into persons(fname) values('Kidf Two');
insert into persons(fname) values('Kidg Two');

insert into persons(fname) values('Dadh Three');
insert into persons(fname) values('Momi Three');

insert into persons(fname) values('Dadj Four');

insert into dependents(parent_id, child_id) values('1', '3');
insert into dependents(parent_id, child_id) values('2', '3');
insert into dependents(parent_id, child_id) values('4', '6');
insert into dependents(parent_id, child_id) values('5', '6');
insert into dependents(parent_id, child_id) values('4', '7');
insert into dependents(parent_id, child_id) values('5', '7');

The following attempt can list all the children but I'm not sure how to
group them into a single string based on their parents.

SELECT DISTINCT c.fname  AS "Children"
FROM persons p, persons c, dependents d
WHERE  d.parent_id = p.person_id AND
       d.child_id  = c.person_id
;

 Children
----------
 Kidc One
 Kidf Two
 Kidg Two


Thanks,

- Chansup