cube统计包含了rollup的统计结果，而且还有其他组合分组结果(小计)，CUBE(n列)，那么分组种类有：
cube分组就是先进行合计(一个不取
)，然后小计(
到
)，最后取标准分组
。
与rollup不同，CUBE计算结果和列的顺序无关，如果列顺序不同，默认的结果排序则不同。
SQL> select a.dname,b.job,sum(b.sal) sumsal from scott.dept a,scott.emp b where a.deptno=b.deptno group by cube(a.dname,b.job); DNAME JOB SUMSAL
-------------- --------- ----------
29025
CLERK 4150
ANALYST 6000
MANAGER 8275
SALESMAN 5600
PRESIDENT 5000
SALES 9400
SALES CLERK 950
SALES MANAGER 2850
SALES SALESMAN 5600
RESEARCH 10875 DNAME JOB SUMSAL
-------------- --------- ----------
RESEARCH CLERK 1900
RESEARCH ANALYST 6000
RESEARCH MANAGER 2975
ACCOUNTING 8750
ACCOUNTING CLERK 1300
ACCOUNTING MANAGER 2450
ACCOUNTING PRESIDENT 5000 已选择18行。 执行计划
----------------------------------------------------------
Plan hash value: 2432972551 -------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 14 | 392 | 5 (20)| 00:00:01 |
| 1 | SORT GROUP BY | | 14 | 392 | 5 (20)| 00:00:01 |
| 2 | GENERATE CUBE | | 14 | 392 | 5 (20)| 00:00:01 |
| 3 | SORT GROUP BY | | 14 | 392 | 5 (20)| 00:00:01 |
| 4 | NESTED LOOPS | | 14 | 392 | 4 (0)| 00:00:01 |
| 5 | TABLE ACCESS FULL | EMP | 14 | 210 | 3 (0)| 00:00:01 |
| 6 | TABLE ACCESS BY INDEX ROWID| DEPT | 1 | 13 | 1 (0)| 00:00:01 |
|* 7 | INDEX UNIQUE SCAN | PK_DEPT | 1 | | 0 (0)| 00:00:01 |
------------------------------------------------------------------------------------------- Predicate Information (identified by operation id):
--------------------------------------------------- 7 - access("A"."DEPTNO"="B"."DEPTNO") 统计信息
----------------------------------------------------------
0 recursive calls
0 db block gets
23 consistent gets
0 physical reads
0 redo size
960 bytes sent via SQL*Net to client
396 bytes received via SQL*Net from client
3 SQL*Net roundtrips to/from client
2 sorts (memory)
0 sorts (disk)
18 rows processed