sql STUFF 分组

1 ---将sql想关的数据放到一个字段里
2 select r.Region_Name,
3 STUFF((select ','+cast(c2.city_name as varchar(10)) [text()]
4 from City c2
5 inner join Region as r2 on c2.Region_id=r.Region_ID
6 where r2.Region_ID = r.Region_ID
7 for xml path('')),1,1,'') city_name
8 from Region as r