Second level Hierarchy Manager

Question

I have a hierarchy like this
A has child B,C
B has child D,E,F
C has child P,Q
D has Child G,H
E has child I,J,K
F has Child L,M
G has child N,O
I need the second level manager from top most node for any child
1st level top most node in the above example is A
2nd level top most node in the above example is B and C
I will give any child as parameter.But it has to return its 2nd level manager.
For eg if my parameter is J it has to return B
if my parameter is Q it has to return C
if my parameter is N it has to return B
Thanks

Answer 1

Hi,
One way is to use a Yo-Yo Query , where you do two CONNECT BYs: one from the bottome up, the next from the top down, like this:
WITH     ancestors     AS
     SELECT     child
     ,     parent
     ,     CONNECT_BY_ISLEAF     AS is_root
     FROM     table_x
     START WITH     child     = 'J'
     CONNECT BY     child     = PRIOR parent
SELECT     child
FROM     ancestors
WHERE     LEVEL     = 3     -- or 4, or whatever
START WITH     is_root     = 1
CONNECT BY     parent     = PRIOR child
;Another way is to use a single CONNECT BY, and get the desired results from SYS_CONNECT_BY_PATH and REGEXP_SUBSTR.