Root node query

Question

Hi
Sample Data:
create table mycust(child_id number(30),parent_id number(30));
insert into mycust values(100000059627549,100000059657962);
insert into mycust values(100000059657962,300006133014350);
insert into mycust values(300006133014350,100000098989898);
insert into mycust values(10000962675,30000350898);
insert into mycust values(30000350898,13089862675);
commit;
I'm try to form a query that would fetch results in following way (to get the root of each child)
like parent of 10000962675 is 30000350898,whose parent in turn is 13089862675
so I want o/p in format . can someone please suggest
child
parent
Root
100000059627549
100000059657962
100000098989898
100000059657962
300006133014350
100000098989898
300006133014350
100000098989898
100000098989898
10000962675
30000350898
13089862675
30000350898
13089862675
13089862675

Answer 1

I think you're looking for this...
SQL> ed
Wrote file afiedt.buf
  1  select child_id
  2        ,parent_id
  3        ,connect_by_root parent_id
  4  from mycust
  5  connect by prior child_id = parent_id
  6* start with parent_id not in (select child_id from mycust)
SQL> /
                        CHILD_ID                        PARENT_ID         CONNECT_BY_ROOTPARENT_ID
                     30000350898                      13089862675                      13089862675
                     10000962675                      30000350898                      13089862675
                 300006133014350                  100000098989898                  100000098989898
                 100000059657962                  300006133014350                  100000098989898
                 100000059627549                  100000059657962                  100000098989898
though you didn't make it easy for us to follow, using such obscure large numbers.
Next time, please use an example that just simplifies it and uses something like 1,2,3,4,5... etc. so it's nice and clear