sql - Oracle hierarchical query record prior to max level record

Question

I have the following Oracle SQL query:

select   id_emp_no,
         LEVEL,
         CONNECT_BY_ISLEAF isleaf
from  my_table  
start with id_emp_no = :x
connect by prior my_mgr = id_emp_no 
ORDER BY level

This produces the following output:

ID_EMP_NO   LEVEL   ISLEAF
11          1       0
22          2       0
33          3       0
44          4       0
55          5       0   <<====
66          6       1

Based on the above output, the actual result ID_EMP_NO that I am specifically after is where ID_EMP_NO = 55, that is the record preceeding the max level and the record prior to ISLEAF equalling 1.

So I only want to return the record where ID_EMP_NO = 55.

Answer 1

Keep in mind that prior is nothing but an operator specifying a value of this column from an upper level of the hierarchy, which means you can use it (almost) anywhere in your query:

SQL Fiddle

select prior id_emp_no 
  from my_table  
 where CONNECT_BY_ISLEAF = 1 
 start with id_emp_no = 11
connect by prior my_mgr = id_emp_no

Results:

| PRIORID_EMP_NO |
------------------
|             55 |