sql查询语句for xml path语法

for xml path作用：将多行的查询结果，根据某一些条件合并到一行。

例如：现在有一张表

执行下面语句

  select [Department],
        (SELECT [Employee]+',' FROM dbo.[People] b WHERE b.[Department]=a.[Department] For XML Path('')) AS Student 
  from [dbo].[People] as a
  group by [Department]

得到如下结果

可以，发现for xml path将，IT和人事的人员进行合并，并且用逗号进行分割。

如果想要获取整个公司的人员，并且用逗号隔开，执行如下语句

select STUFF((select ','+[Employee] 
FROM (
    select [Employee]
    from dbo.[People] as a
) as c FOR XML PATH('')),1,1,'')

得到如下结果