hiearchy in sql

hi,

i want the results of each where clause in a new col

for eg if there are 4 roles viz a - b- c- d

b reports to a ,c reports to b ,d reports to c

also there may be case like d direcltly reports to a or c reporting to to a and so on

i want to generate a report having all a's , then the b's rep to a, then the c's reporting to b and so on ..

please suggestPlease, show me column names, data sample and desired result.

Thank you.|||regionstatelocation dsa RM I.e a TM I.e. b TL I.e c S E I.e d
Westmahbomabcpqrs
q1s1
s2
westmahbomxyzp1q2r1
r2s3
s4
p3s5
north ndh ndh rrr

the above is the ex how i want my data , the reporting shouls be from highest to lowest.
i have tried functions also but didnot get the expected results