Thanks for the question regarding "connect by ", versi

-Peter
Can I get the parent position w.r.t. to the rownum? March 5, 2004 - 4pm Central time zone
Bookmark | Bottom | Top
Reviewer: Peter Tran from Houston, TX USA
Hi Tom,
Is it possible for me to generate the ParentPosition index w.r.t. to the assigned ROWNUM? Of
course, ROWNUM starts at 1, but my example below is using base 0. Either way, you can see where
I'm getting at with the example below.
Currently, I'm doing this mapping in code. It would be much better if I can do this within SQL.
Thanks,
-Peter
ROWNUM ENAME EMPNO MGR ParentPos
------ --------------- ---------- ---------- -------------
0 KING 7839 7839 0
1 JONES 7566 7839 0
2 FORD 7902 7566 1
3 SMITH 7369 7902 2
4 SCOTT 7788 7566 1
5 ADAMS 7876 7788 4
6 BLAKE 7698 7839 0
7 ALLEN 7499 7698 6
8 WARD 7521 7698 6
9 MARTIN 7654 7698 6
10 TURNER 7844 7698 6
11 JAMES 7900 7698 6
12 CLARK 7782 7839 0
13 MILLER 7934 7782 12
Followup March 5, 2004 - 7pm Central time zone:
what is "parentPos"
ParentPos March 6, 2004 - 5pm Central time zone Bookmark | Bottom | Top
Reviewer: Peter Tran from Houston, TX USA
ParentPos is the RowNum value of the parent.
King is the parent of Jones, Blake, and Clark which is why ParentPos for them is 0.
Blake is the parent of Alan, Ward, Martin, Turner, and James, so you see their ParentPos is 6
because Blake's RowNum is 6.
Thanks,
-Peter
Followup March 6, 2004 - 8pm Central time zone:
scott@ORA9IR2> select rnum, ename, empno, mgr,
2 substr( scbp2, 1, instr(scbp2,',')-1 ) parentpos
3 from (
4 select a.*,
5 substr( scbp, instr(scbp, ',', -1, 2 )+1 ) scbp2
6 from (
7 select rownum-1 rnum, rpad( ' ', 2*level, ' ' ) || ename ename, empno, mgr,
8 sys_connect_by_path( rownum-1, ',' ) scbp
9 from emp
10 start with mgr is null
11 connect by prior empno = mgr
12 ) a