SQL查询将行转换为列

Question

我在SQL Server 2008中具有下表：

[ID] [Filiale] [Mitarbeiter]
1    01        M眉ller
2    01        Meier
3    01        Schmidt
4    02        Schulz
5    02        Schr枚der

我需要创建以下输出的查询：

[Filiale] [Mitarbeiter1] [Mitarbeiter2] [Mitarbeiter3] [Mitarbeiter4] [Mitarbeiter5]
01        M眉ller         Meier          Schmidt        NULL           NULL
02        Schulz         Schr枚der       NULL           NULL           NULL

列可以固定为[Mitarbeiter1]-[Mitarbeiter5]，因为每个Filiale的行数不能超过5行。

非常感谢您的帮助！

Answer 1

使用SQL Server
2008，将Pivot和Rank函数组合在一起，可以为每个雇员数量提供理想的结果。首先，我们为每个分支中的每个员工分配一个ID，从每个新分支中的1开始，然后使用透视运算符来翻转结果

create table data
(
id int, 
branch int, 
employee varchar(20)
)

 insert into data (id, branch, employee) values
 (1, 1, 'M眉ller'),
 (2, 1, 'Meler'),
 (3, 1, 'Schmidt'),
 (4, 1, 'Schultz'),
 (5, 2, 'Schr枚der'),
 (6, 2, '=tg= Thomas'),
 (7, 3, 'Stephan')


select branch, [1] as emp1, [2] as emp2, [3] as emp3, [4] as emp4, [5] emp5 
from
(
  select ROW_NUMBER() over (partition by branch order by id) employee_branch_id, branch, employee 
    from data
) data_with_employee_branch_id -- assign a number from 1 to n for each emplyee in the branch 
pivot 
(
  max(employee) --it must be a aggregat, since we have only one row the max of a string will be the string
  for employee_branch_id in ( [1], [2], [3], [4], [5] )
) as data_pvt