SQL Server使用FOR XML PATH按组连接多行

Question

我有一个findhighest_secondstep这样的数据表：

id  department  top_employee    highest_salary  rownumber1
-----------------------------------------------------------
 5  Finance         Shane           6300            1
10  Finance         Laura           6300            1
 7  HR              Vik             7200            1
 3  IT              Kate            7500            1
14  Marketing       Elice           6800            1
 6  Sales           Shed            8000            1

我想返回一个包含列部门，top_employee和highest_salary的表，而我知道在财务部门，我们有两个人的工资相同。所以我想展示所有这些。

SELECT 
    hs.department AS department,
    top_employee = STUFF((SELECT ', ' + top_employee
                          FROM findhighest_secondstep 
                          FOR XML PATH('')), 1, 1, '')                   
FROM 
    findhighest_secondstep hs
GROUP BY 
    hs.department

这就是我得到的：

department    top_employee
--------------------------------------------------
Finance       Shane, Laura, Vik, Kate, Elice, Shed
HR            Shane, Laura, Vik, Kate, Elice, Shed
IT            Shane, Laura, Vik, Kate, Elice, Shed
Marketing     Shane, Laura, Vik, Kate, Elice, Shed
Sales         Shane, Laura, Vik, Kate, Elice, Shed

我想要的是：

department  top_employee    highest_salary
---------------------------------------------
Finance     Shane, Laura    6300
HR          Vik             7200
IT          Kate            7500
Marketing   Elice           6800
Sales       Shed            8000

Answer 1

您需要一个相关的子查询：

SELECT hs.department AS department,
       STUFF( (SELECT ', ' + top_employee
               FROM findhighest_secondstep hs2
               WHERE hs2.department = hs.department
               FOR XML PATH('')
              ), 1, 2, ''
            ) as top_employees                   
FROM findhighest_secondstep hs
GROUP BY hs.department