need one query

[VenuGopal Papasani]

Hi all,
   I Have a table with followin structure where i have orgunit and parent
and value


orgunit                    parent                           value

12                           10                                  x
15                            12                                 y
16                            12                                 z
17                            12                                 p

                Now here 15,16, and 17 are the children of 12 and 12 is the
child of 10.Now i need a query which gives the sum of all the children  of
12 and nturn 12 itself . i.e I need the sum(values(15+16+17+12)).Is there a
query which gives the sum of all these.It will be very helpful if i am able
to get it in a single query.

Thanks and regards,
venu.