乱玩的;
--create database mytest --建表 create table S ( sno char(2), sname varchar(8), sex varchar(29), age int, ); create table SC( sno char(2), cno char(2), grade int, ); --for test create table T_a ( id int identity(1,1), aname char(2), ); insert T_a (aname) values ('aa'); insert T_a (aname) values ('1'); insert T_a (aname) values ('2'); insert T_a (aname) values ('3'); insert T_a (aname) values ('4'); select * from T_a; --insert T_a (T_aname) /* create table a ( aa int identity(1,1), bb char, ); create table b ( aa int identity(1,1), bb char, ); */ --插入 insert S (sno, sname, sex, age) values ('01', '张三', '男', 20); insert S (sno, sname, sex, age) values ('02', '李四', '女', 20); insert S (sno, sname, sex, age) values ('03', '王五', '男', 22); insert S (sno, sname, sex, age) values ('04', '赵六', '女', 19); insert SC (sno, cno, grade) values ('01', '01', 10); insert SC (sno, cno, grade) values ('02', '02', 20); insert SC (sno, cno, grade) values ('03', '03', 30); insert SC (sno, cno, grade) values ('04', '04', 40); --显示 select * from S; select * from SC; select s1.sno, s1.sname, s2.sno,s2.sname from S s1 join S s2 on s1.sname = s2.sname where s1.sno < s2,sno; drop table S; drop table SC; drop table T_a;