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一.定义表变量
insert into @t1 (userid,username,cityname) values (1,'a','上海')
insert into @t1 (userid,username,cityname) values (2,'b','北京')
insert into @t1 (userid,username,cityname) values (3,'c','上海')
insert into @t1 (userid,username,cityname) values (4,'d','北京')
insert into @t1 (userid,username,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, 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('')),1,1,'')
效果图:
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数据库SQL---数据库、基本表、视图、索引的定义、修改、删除
在 Azure CentOS VM 中配置 SQL Server 2019 AG - (上)
在 Azure CentOS VM 中配置 SQL Server 2019 AG - (下)
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