Help in writing stored procedrue

Question

I have a table with records like below
ccn item sub_item
1 101a 102a
2 102a 103a
3 103a 104a
4 100x 100y
5 100y 100z
6 101b 101c
and need to load above data into other table like below
p_id p_item p_sub_item p_old_item f_code f_seq_no
1 101a 102a (null) 0001 01
2 102a 103a 101a 0001 02
3 103a 104a 102a 0001 03
4 104a (null) 103a 0001 04
5 100x 100y (null) 0002 01
6 100y 100z 100x 0002 02
7 100z (null) 100y 0002 03
8 101b 101c ( null ) 0003 01
9 101c (null _ 101b 0003 02
here ccn,p_id,f_code,f_seq_no number type
item,sub_item ,p_item,p_sub_item,p_old_item varchar type
Help me in writing the procedure

Answer 1

Here it is. Now you can just do an insert as select to get it in the target table.
SQL> with t as (select 1 as ccn, '101a' as item, '102a' as sub_item from dual union
  2             select 2, '102a', '103a' from dual union
  3             select 3, '103a', '104a' from dual union
  4             select 4, '100x', '100y' from dual union
  5             select 5, '100y', '100z' from dual union
  6             select 6, '101b', '101c' from dual)
  7  -- end of test data
  8  select rownum as p_id, p_item, p_sub_item, p_old_item, sum(f_code) over (order by rownum) as f_code, f_seq_no
  9  from (
10  select item as p_item
11        ,sub_item as p_sub_item
12        ,(select item from t t2 where t2.sub_item = t.item) as p_old_item
13        ,decode(level,1,1) as f_code
14        ,level as f_seq_no
15  from (select ccn, item, sub_item
16        from t
17        union
18        select ccn+0.5, sub_item, null
19        from t
20        where not exists(select 1 from t t2 where t2.item = t.sub_item)
21       ) t
22  connect by item = prior sub_item
23  start with ccn in
24       (select ccn
25        from t
26        where not exists(select 1 from t t2 where t2.sub_item = t.item)
27        )
28        order by ccn
29  )
30  /
      P_ID P_IT P_SU P_OL     F_CODE   F_SEQ_NO
         1 101a 102a               1          1
         2 102a 103a 101a          1          2
         3 103a 104a 102a          1          3
         4 104a      103a          1          4
         5 100x 100y               2          1
         6 100y 100z 100x          2          2
         7 100z      100y          2          3
         8 101b 101c               3          1
         9 101c      101b          3          2
9 rows selected.
SQL>Message was edited by:
blushadow
edited to complete the solution