Question

要求

如何为每件产品选择/获得月 - 年（MON-YY）明智的结果？我试着写一个查询：

SELECT * FROM
(
    SELECT  PRODUCT_CODE AS PRODUCT
    ,       EXTRACT (MONTH FROM (UPDATED_DATE))  AS month_num
    ,       PRODUCT_CODE
    FROM    Test_Pivot
)
PIVOT     (    COUNT (PRODUCT_CODE)
          FOR  month_num  IN (  1 AS jan,  2 AS feb,  3 AS mar,  4 As apr,  5 as may,  6 AS jun,
                                7 AS jul,  8 AS aug,  9 AS sep,  10 As oct,  11 as nov,  12 AS dec
                             )                             
          );

我正在获得结果，但它无论年份如何都能完全计算。我不知道如何修改SQL以限制从当前月份开始的最近6个月的计数。我希望Months列动态显示为'MON-YY'，而不仅仅是'MON'，如下面的示例格式所述

   PRODUCT  JAN-16  FEB-16  MAR-16  APR-16  MAY-16  JUN-16
-------------------------------------------------------------
      D        1       0       1       0       0       2
      A        1       0       2       0       4       1
      B        1       0       2       1       1       0
      C        0       0       1       0       4       1

以上示例中的数据仅供参考（6月16日为当月）

样本表

CREATE TABLE Test_Pivot (
  id            NUMBER,
  customer_id   NUMBER,
  product_code  VARCHAR2(5),
  quantity      NUMBER,
  Updated_date          date
);

示例数据

INSERT INTO Test_Pivot VALUES (1, 1, 'A', 10, sysdate);
INSERT INTO Test_Pivot VALUES (2, 1, 'B', 20, sysdate-50);
INSERT INTO Test_Pivot VALUES (3, 1, 'C', 30, sysdate-90);
INSERT INTO Test_Pivot VALUES (4, 2, 'A', 40, sysdate-75);
INSERT INTO Test_Pivot VALUES (5, 2, 'C', 50, sysdate-25);
INSERT INTO Test_Pivot VALUES (6, 3, 'A', 60, sysdate-20);
INSERT INTO Test_Pivot VALUES (7, 3, 'B', 70, sysdate-80);
INSERT INTO Test_Pivot VALUES (8, 3, 'C', 80, sysdate-40);
INSERT INTO Test_Pivot VALUES (9, 3, 'D', 90, sysdate-5);
INSERT INTO Test_Pivot VALUES (10, 4, 'A', 100, sysdate-35);
INSERT INTO Test_Pivot VALUES (11, 2, 'A', 40, sysdate-75);
INSERT INTO Test_Pivot VALUES (12, 2, 'C', 50, sysdate-25);
INSERT INTO Test_Pivot VALUES (13, 3, 'A', 60, sysdate-20);
INSERT INTO Test_Pivot VALUES (14, 3, 'B', 70, sysdate-80);
INSERT INTO Test_Pivot VALUES (15, 3, 'C', 80, sysdate-40);
INSERT INTO Test_Pivot VALUES (16, 3, 'D', 90, sysdate-5);
INSERT INTO Test_Pivot VALUES (17, 4, 'A', 100, sysdate-35);
INSERT INTO Test_Pivot VALUES (18, 3, 'B', 60, sysdate-400);
INSERT INTO Test_Pivot VALUES (19, 3, 'C', 70, sysdate-365);
INSERT INTO Test_Pivot VALUES (20, 3, 'D', 80, sysdate-450);
INSERT INTO Test_Pivot VALUES (21, 3, 'A', 90, sysdate-500);
INSERT INTO Test_Pivot VALUES (22, 4, 'A', 100, sysdate-555);
INSERT INTO Test_Pivot VALUES (23, 2, 'B', 40, sysdate-543);
INSERT INTO Test_Pivot VALUES (24, 2, 'B', 50, sysdate-150);
INSERT INTO Test_Pivot VALUES (25, 3, 'D', 60, sysdate-151);

Answer 1

尝试：

SELECT * FROM
(
    SELECT  PRODUCT_CODE AS PRODUCT
    ,       EXTRACT (YEAR FROM (UPDATED_DATE))  AS year_num
    ,       EXTRACT (MONTH FROM (UPDATED_DATE))  AS month_num
    ,       PRODUCT_CODE
    FROM    Test_Pivot
)
PIVOT     (    
          COUNT (PRODUCT_CODE)
          FOR  (year_num, month_num)  IN (  
               (2016,1) AS jan_16, (2016,2) AS feb_16, (2016,3) AS mar_16,
               (2016,4) AS apr_16, (2016,5) AS may_16, (2016,6) AS jun_16,
               (2016,7) AS jul_16, (2016,8) AS aug_16, (2016,9) AS sep_16,
               (2016,10) AS oct_16, (2016,11) AS nov_16, (2016,12) AS dev_16
          )
);

在静态SQL中，您无法使“动态显示”和“自动调整为仅显示最近6个月”的年份和月份，PIVOT子句不是动态的，您必须列出所有值对：{{1}在它里面但是，您可以进行动态查询（使用动态SQL），但这是除此答案之外的单独主题。

======编辑=============
如果你想要的结果只有6个月，并且你不希望确切的月份名称作为列名（2月，4月等），那么你可以使用这样的查询：

(2014,1) ...... (2027,12)

Oracle SQL选择过去6个月的月份产品数量

1 个答案: