Why does this happen ?
SQL> SELECT 1,2,3 FROM DUAL
2 GROUP BY CUBE(1,2,3);
1 2 3
---------- ---------- ----------
1 2 3
SQL> SELECT * FROM
2 (SELECT 1,2,3 FROM DUAL
3 GROUP BY CUBE(1,2,3)
4 );
1 2 3
---------- ---------- ----------
1 2 3
1 2 3
1 2 3
1 2 3
1 2 3
1 2 3
1 2 3
1 2 3
8 ROWS SELECTED