Group by at each level

Question

Hi Guru's,
Many Thanks for Previous help.
I have set of input and i need the output in some manner.
I tried to solve it but not able to think how can i do this...i tried to use cursor and loop concept  but values in xyz column increase then nos. of cursor also get increase.
Please help me on this.
Specially the values highlighted in bold .
Input:
abc
xyz
Numerator
Denominator
a1
a
12
23
a1
b
13
24
a1
c
18
29
a2
d
18
29
a2
e
12
11
output:
cde
lmn
Numerator
Denominator
a1
a
12
23
a1
b
13
24
a1
a,b
12+13
23+24
a1
a,c
12+18
23+29
a1
b,c
13+18
24+29
a1
a,b,c
12+13+18
23+24+29
a2
e
12
11
a2
d
18
29
a2
e,d
12+18
11+29
Thanks,

Answer 1

may be...
SQL> with t
  2  as
  3  (
  4  select 'a1' abc, 'a' xyz, 12 numerator, 23 denominator from dual
  5  union all
  6  select 'a1' abc, 'b' xyz, 13 numerator, 24 denominator from dual
  7  union all
  8  select 'a1' abc, 'c' xyz, 18 numerator, 29 denominator from dual
  9  union all
10  select 'a2' abc, 'd' xyz, 18 numerator, 29 denominator from dual
11  union all
12  select 'a2' abc, 'e' xyz, 12 numerator, 11 denominator from dual
13  )
14   select distinct abc
15        , ltrim(sys_connect_by_path(xyz_1, ','), ',') xyz
16        , ltrim(sys_connect_by_path(nu, '+'), '+') numerator
17        , ltrim(sys_connect_by_path(de, '+'), '+') denominator
18     from (
19            select abc
20                 , xyz
21                 , regexp_substr(xyz, '[^,]+', 1, level) xyz_1
22                 , regexp_substr(nu, '[^+]+', 1, level) nu
23                 , regexp_substr(de, '[^+]+', 1, level) de
24                 , row_number()
25                      over(partition by abc, xyz
26                        order by regexp_substr(xyz, '[^,]+', 1, level)) rno
27              from (
28                      select abc
29                           , ltrim(sys_connect_by_path(xyz, ','),',') xyz
30                           , ltrim(sys_connect_by_path(to_char(numerator), '+'),'+') nu
31                           , ltrim(sys_connect_by_path(to_char(denominator), '+'),'+') de
32                        from t
33                     connect
34                          by nocycle xyz != prior xyz
35                         and abc = prior abc
36                   )
37           connect
38                by level <= length(xyz) - length(replace(xyz, ',')) + 1
39               and prior xyz = xyz
40               and prior abc = abc
41               and prior sys_guid() is not null
42          )
43    where connect_by_isleaf = 1
44    start
45     with rno = 1
46  connect
47       by abc = prior abc
48      and xyz = prior xyz
49      and rno = prior rno + 1
50    order
51       by abc
52        , length(xyz)
53        , xyz;
ABC   XYZ        NUMERATOR            DENOMINATOR
a1    a          12                   23
a1    b          13                   24
a1    c          18                   29
a1    a,b        12+13                23+24
a1    a,c        12+18                23+29
a1    b,c        13+18                24+29
a1    a,b,c      12+13+18             23+24+29
a2    d          18                   29
a2    e          12                   11
a2    d,e        18+12                29+11
10 rows selected.
SQL>