测试数据脚本
CREATE TABLE Atable ( S# INT, Sname nvarchar(32), Sage INT, Sfrom nvarchar(8) ) insert into Atable select 1,N'李四',18,N'A' union all select 2,N'tom',19, N'A' union all select 3,N'刘一',17,N'A' union all select 4,N'jack',18,N'A' CREATE TABLE Btable ( S# INT, Sname nvarchar(32), Sage INT, Sfrom nvarchar(8) ) insert into Btable select 1,N'刘一',18,N'B' union all select 2,N'钱二',19,N'B' union all select 3,N'张三',17,N'B' union all select 4,N'李四',18,N'B'