How to get sum in new row (not in a new column) in the query output ?

Question

There are values in a table like this:
A B C D
DEsc1 ID1 15 45
DEsc2 ID1 10 67
DEsc3 ID2 12 34
Desc4 ID2 19 32
How to achieve this output :
A B C D
DEsc1 ID1 15 45
DEsc2 ID1 10 67
--- ID1 25 112 <--- Sum of two rows corresponding to C and D whose B column is same
DEsc3 ID2 12 34
Desc4 ID2 19 32
Desc5 ID2 10 12
----- ID2 41 78 <---- Sum of three rows corresponding to C and D whose B column is same

Answer 1

SQL>WITH t AS
  2       (SELECT 'DEsc1' AS a, 'ID1' AS b, 15 AS c, 45 AS d FROM DUAL
  3        UNION ALL
  4        SELECT 'DEsc2', 'ID1', 10, 67 FROM DUAL
  5        UNION ALL
  6        SELECT 'DEsc3', 'ID2', 12, 34 FROM DUAL
  7        UNION ALL
  8        SELECT 'Desc4', 'ID2', 19, 32 FROM DUAL)
  9  SELECT   DECODE(GROUPING(a || ' ' || c || ' ' || d), 0, TO_CHAR(MAX(a)), '-----') AS a,
10           MAX(b) AS b, SUM(c) AS c, SUM(d) AS d
11      FROM t
12  GROUP BY b, ROLLUP(a || ' ' || c || ' ' || d);
A     B            C          D
DEsc1 ID1         15         45
DEsc2 ID1         10         67
----- ID1         25        112
DEsc3 ID2         12         34
Desc4 ID2         19         32
----- ID2         31         66Urs