SQL group BY 合并字段用逗号隔开

1.关联多表后 根据某个字段作为分组条件,其他合并到新列中,效果如下图

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代码:

select KUserID, KOrderID=stuff((select ','+Convert(varchar(10),KOrderID) from VOrder2 t where KUserID=tb.KUserID for xml path('')), 1, 1, '')

from VOrder2 tb
group by KUserID

2.单个表直接转换单列合并

select stuff((select ','+Convert(varchar(10),PID)  from AA  where State=1 for xml path('')), 1, 1, '') as PID