在SQL中透视数据

Question

在MSSQL中将表Table2Dimension转换为Table DesiredTable的正确语法是什么？

Answer 1

由于您使用的是SQL Server，因此可以使用PIVOT函数获取结果：

select [row], [1], [2], [3]
from
(
  select [row], col, value
  from Table2Dimension
) d
pivot
(
  max(value)
  for col in ([1], [2], [3])
) piv;

见SQL Fiddle with Demo。这给出了结果：

| ROW | 1 | 2 | 3 |
|-----|---|---|---|
|   1 | 1 | 2 | 3 |
|   2 | 4 | 5 | 6 |
|   3 | 7 | 8 | 9 |

Answer 2

select row,
       sum(case when col = 1 then value end) as [1],
       sum(case when col = 2 then value end) as [2],
       sum(case when col = 3 then value end) as [3]
from your_table
group by row