如何将列转换为行？

Question

我有下表。 COLUMN_NAME和DATA_TYPE是列名，下面是值。

SELECT SALESPERSONID
FROM SALES
GROUP BY SALESPERSONID
HAVING COUNT(*) >= 3

我想将该表转换为下表：

COLUMN_NAME      DATA_TYPE
employee_id      int
employee_name    varchar
employee_age     int

Answer 1

使用透视：

declare @t table(COLUMN_NAME varchar(max), DATA_TYPE varchar(max))
insert into @t values
('employee_id',      'int'),
('employee_name',    'varchar'),
('employee_age',     'int')

select * from @t
pivot(max(DATA_TYPE) for COLUMN_NAME in([employee_id],[employee_name],[employee_age]))p

输出：

employee_id employee_name   employee_age
int         varchar         int