Question

我有两张桌子。

学生表

物业表

结果表

如何从Property表中获取Student Table的值和列的属性ID并将其合并到Result表中？

任何建议都会有所帮助。

更新＃1：

我尝试过使用Christian Moen的建议，这就是我得到的。

Answer 1

您需要先UNPIVOT Student个列，才能将一列中的列（属性名称）作为行。然后使用基于属性名称的join表Property，如下所示：

WITH UnPivoted
AS
(
  SELECT ID, value,col
  FROM 
  (
    SELECT ID,
      CAST(Name AS NVARCHAR(50)) AS Name, 
      CAST(Class AS NVARCHAR(50)) AS Class,
      CAST(ENG AS NVARCHAR(50)) AS ENG,
      CAST(TAM AS NVARCHAR(50)) AS TAM,
      CAST(HIN AS NVARCHAR(50)) AS HIN,
      CAST(MAT AS NVARCHAR(50)) AS MAT,
      CAST(PHY AS NVARCHAR(50)) AS PHY
    FROM Student 
  ) AS s
  UNPIVOT
  (value FOR col IN 
        ([Name], [class], [ENG], [TAM], [HIN], [MAT], [PHY])
  )AS unpvt
)
SELECT 
  ROW_NUMBER() OVER(ORDER BY u.ID,PropertyID) AS ID,
  p.PropertyID,
  u.Value,
  u.ID AS StudID
FROM Property AS p
INNER JOIN UnPivoted AS u ON p.PropertyName = u.col;

对于第一个ID，我使用排名函数ROW_NUMBER()来生成此序列ID。

这将给出您正在寻找的确切结果。

<强> Results ：

| ID | PropertyID |  Value | StudID |
|----|------------|--------|--------|
|  1 |          1 |   Jack |      1 |
|  2 |          2 |     10 |      1 |
|  3 |          3 |     89 |      1 |
|  4 |          4 |     88 |      1 |
|  5 |          5 |     45 |      1 |
|  6 |          6 |    100 |      1 |
|  7 |          7 |     98 |      1 |
|  8 |          1 |   Jill |      2 |
|  9 |          2 |     10 |      2 |
| 10 |          3 |     89 |      2 |
| 11 |          4 |     99 |      2 |
| 12 |          5 |    100 |      2 |
| 13 |          6 |     78 |      2 |
| 14 |          7 |     91 |      2 |
| 15 |          1 | Trevor |      3 |
| 16 |          2 |     12 |      3 |
| 17 |          3 |    100 |      3 |
| 18 |          4 |     50 |      3 |
| 19 |          5 |     49 |      3 |
| 20 |          6 |     94 |      3 |
| 21 |          7 |    100 |      3 |
| 22 |          1 |    Jim |      4 |
| 23 |          2 |      8 |      4 |
| 24 |          3 |    100 |      4 |
| 25 |          4 |     91 |      4 |
| 26 |          5 |     92 |      4 |
| 27 |          6 |    100 |      4 |
| 28 |          7 |    100 |      4 |

Answer 2

其他选项是使用apply如果您不想unpivot方式

select row_number() over (order by (select 1)) ID, p.PropertyID [PropID], a.Value, a.StuID 
from Student s
cross apply
(
    values (s.ID, 'Name', s.Name),
           (s.ID, 'Class', cast(s.Class as varchar)),
           (s.ID, 'ENG', cast(s.ENG as varchar)),
           (s.ID, 'TAM', cast(s.TAM as varchar)),
           (s.ID, 'HIN', cast(s.HIN as varchar)),
           (s.ID, 'MAT', cast(s.MAT as varchar)),
           (s.ID, 'PHY', cast(s.PHY as varchar))
) as a(StuID, Property, Value)
join Property p on p.PropertyName = a.Property

如何获取行和列的值

2 个答案: