一.定义表变量
代码如下:
DECLARE @T1 table(
UserID int,
UserName nvarchar(50),
CityName nvarchar(50)
);
insert into @T1 (UserID,UserName,CityName) values (1,'a','上海')
insert into @T1 (UserID,CityName) values (2,'b','北京')
insert into @T1 (UserID,CityName) values (3,'c',CityName) values (4,'d',CityName) values (5,'e','上海')
select * from @T1
-----最优的方式
SELECT CityName,STUFF((SELECT ',' + UserName FROM @T1 subTitle WHERE CityName=A.CityName FOR XML PATH('')),1,'') AS A
FROM @T1 A
GROUP BY CityName
----第二种方式
SELECT B.CityName,LEFT(UserList,LEN(UserList)-1)
FROM (
SELECT CityName,(SELECT UserName+',' FROM @T1 WHERE CityName=A.CityName FOR XML PATH('')) AS UserList
FROM @T1 A
GROUP BY CityName
) B
stuff(select ',' + fieldname from tablename for xml path('')),'')
