如何在sql查询中将多列设置为行

Question

我想使用 SQL Server 将列转换为行。我已经尝试过 unpivot 但没有足够的知识使它只能制作一列

SELECT Unit,Excess_Reactivity ,Refuelling_required,MBP,MCP ,CPPF,Date FROM yourTable // select statement

//insert  to check data
INSERT INTO yourTable
    (Unit,Excess_Reactivity ,Refuelling_required,MBP ,MCP ,CPPF ,Date)
VALUES
    ('TAP-4','52','test1','12','96','35','2019-06-11 00:00:00.000')

INSERT INTO yourTable
    (Unit,Excess_Reactivity ,Refuelling_required,MBP ,MCP ,CPPF ,Date)
VALUES
    ('TAP-2','52','test1','12','96','35','2019-06-11 00:00:00.000')

INSERT INTO yourTable
    (Unit,Excess_Reactivity ,Refuelling_required,MBP ,MCP ,CPPF ,Date)
VALUES
    ('TAP-3','52','test1','12','96','35','2019-06-11 00:00:00.000')

这是桌子

+--------+--------+---------+-----+-----+------+------------+
|  UNit  | excess | refuell | MBp | MCP | CPPF |    DATE    |
+--------+--------+---------+-----+-----+------+------------+
| TAPS-4 |     52 | test1   |  12 |  96 |   35 | 11/06/2019 |
| TAPS-3 |     52 | test1   |  13 |  96 |   35 | 11/06/2019 |
| TAPS-2 |     52 | test1   |  42 |  96 |   35 | 11/06/2019 |
| TAPS-1 |     52 | test1   |  18 |  96 |   35 | 11/06/2019 |
+--------+--------+---------+-----+-----+------+------------+

我想要这样如下图：

Values   TAPS-4  TAPS-3  TAPS-2 TAPS-1
--------------------------------------
excess    52      52     52      52
MBp       12      13     42      18
MCP       96      96     96      96
CPPF      35      35     35      35

Answer 1

• 首先您需要取消透视表，注意您需要将数据转换为相同类型，因为每个数据都将转到同一列。
• 然后你可以转向你想要的结果。
• 如果需要将其转换回原始数据类型。

SQL FIDDLE

WITH unpvt as (
  SELECT Unit, Attribute, Vals
  FROM ( SELECT Unit, 
                cast(excess as nvarchar(100)) as excess, 
                cast(MBp as nvarchar(100)) as MBp, 
                cast(MCP as nvarchar(100)) as MCP,  
                cast(CPPF as nvarchar(100)) as CPPF
         FROM Table1) as p
  UNPIVOT
       (Vals FOR Attribute in (excess, MBp, MCP, CPPF)
       ) as unpvt
)
SELECT Attribute, [TAPS-4],  [TAPS-3], [TAPS-2], [TAPS-1]
FROM ( SELECT Unit, Attribute, Vals
       FROM unpvt) p 
PIVOT (
         MAX(Vals) FOR  Unit IN 
         ([TAPS-4], [TAPS-3], [TAPS-2], [TAPS-1])
      ) pvt

输出

| Attribute | TAPS-4 | TAPS-3 | TAPS-2 | TAPS-1 |
|-----------|--------|--------|--------|--------|
|      CPPF |     35 |     35 |     35 |     35 |
|    excess |     52 |     52 |     52 |     52 |
|       MBp |     12 |     13 |     42 |     18 |
|       MCP |     96 |     96 |     96 |     96 |

注意：在 sql fiddle 中尝试SELECT * FROM unpvt 以查看中间结果。