SQL三种语言(二)
(sid,age) values(2,13)
insert intostudent3(sid,age) values(3,14)
update student3 set age=age+1
--SELECT 要看的列 FROM 表名,表名
/*
要看的列
1. * 表示所有的列都要看
2. sname,age我只看这两个列
*/
select *from student
select sid from student
select sname from student
select sid,sname from student
select sid 编号,sname 姓名from student--别名
--排序orderby
select *from student order by sid --默认按升序排列
select *from student order by sid desc--按降序排列
select *from student order by sid asc--按升序排列