帶有多個列的oracle匯總功能

Question

我有一個簡單的查詢：

WITH data(val1, val2, val3) AS
     ( SELECT 'a' ,'a-details' ,'1' FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by rollup(val1, val2);

我得到這樣的輸出：

VAL1                             VAL2                                    TOT
-------------------------------- -------------------------------- ----------
a                                a-details                                 1 
a                                                                          1 
b                                b-details                                 2 
b                                                                          2 
c                                c-details                                 3 
c                                                                          3 
Total Result                                                               6 

但我需要這樣的輸出：

VAL1                             VAL2                                    TOT
-------------------------------- -------------------------------- ----------
a                                a-details                                 1 
b                                b-details                                 2 
c                                c-details                                 3 
Total Result                                                               6 

提前致謝。

Answer 1

我發現使用GROUPING SET子句指定所需的確切集合要容易得多：

WITH data(val1, val2, val3) AS
     ( SELECT 'a' ,'a-details' ,'1' FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by grouping sets ((val1, val2),());

我懷疑它會更有效，因為它直接指定要計算的級別。

http://sqlfiddle.com/#!4/8301d/3

CUBE和ROLLUP對於自動生成大量聚合級別（例如，維度層次結構中的每個級別）非常有用，如果您想從生成的大型CUBE中消除一小部分級別的子集，可能會使用GROUPING ID設置，但是GROUPING SET是專門用於指定特定聚合級別的。

Answer 2

GROUPING_ID表達式

您可以使用GROUPING_ID表達式過濾所需的小計級別：

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by ROLLUP(val1, val2)
HAVING GROUPING_ID(val1, val2) IN (0, 3);

輸出：

NVL(VAL1,'TOTALRESULT') VAL2             TOT
----------------------- --------- ----------
a                       a-details          1 
b                       b-details          2 
c                       c-details          3 
Total Result                               6

GROUPING_ID對於沒有小計的行返回0，對於第一級返回1，依此類推，我們可以看一下它返回的值：

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot,
     GROUPING_ID(val1, val2) AS grp_id
from data
group by ROLLUP(val1, val2);

NVL(VAL1,'TOTALRESULT') VAL2             TOT     GRP_ID
----------------------- --------- ---------- ----------
a                       a-details          1          0 
a                                          1          1 
b                       b-details          2          0 
b                                          2          1 
c                       c-details          3          0 
c                                          3          1 
Total Result                               6          3

檢查SQLFiddle

有關匯總和相關主題的更多信息： Tim Hall關於匯總和多維數據集

（ 編輯 ）

分組功能

關於評論。 您可以使用GROUPING函數：

GROUPING-接受單個列作為參數，如果該列包含由ROLLUP或CUBE操作作為小計的一部分生成的空值，則返回“ 1”；對於任何其他值（包括存儲的空值），則返回“ 0”。

返回值的示例：

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot,
     grouping(val1),
     grouping(val2)
from data
group by ROLLUP(val1, val2);

輸出：

NVL(VAL1,'TOTALRESULT') VAL2             TOT GROUPING(VAL1) GROUPING(VAL2)
----------------------- --------- ---------- -------------- --------------
a                       a-details          1              0              0 
a                                          1              0              1 
b                       b-details          2              0              0 
b                                          2              0              1 
c                       c-details          3              0              0 
c                                          3              0              1 
Total Result                               6              1              1

因此，您的查詢應如下所示：

WITH data AS
     ( SELECT 'a' AS val1 ,'a-details' AS val2 , '1' AS val3 FROM DUAL
     UNION ALL
     SELECT 'b' ,'b-details' ,'2' FROM DUAL
     UNION ALL
     SELECT 'c' ,'c-details' ,'3' FROM DUAL
     )
SELECT NVL(val1,'Total Result'),
     val2,
     SUM(val3) tot
from data
group by ROLLUP(val1, val2)
HAVING GROUPING(val1) = 1
   OR (GROUPING(val1) + GROUPING(val2) = 0);

輸出：

NVL(VAL1,'TOTALRESULT') VAL2             TOT
----------------------- --------- ----------
a                       a-details          1 
b                       b-details          2 
c                       c-details          3 
Total Result                               6

在此處使用AskTom的GROUPING功能的想法。