--创建数据库
create database ios
--使用数据库
use ios
--创建数据表
create table student
(
stuid int primary key autoincrement,
stuname varchar(20),
stupwd varchar(20)
)
--查询所有信息
select * from student
--增加信息
insert into student(stuname,stupwd)
values ('lisi','123456')
--修改
update student set stuname = '李四'
where stuid = 1
update student set stuname = '李四',stupwd='Sd123'
where stuid = 1
--删除
delete from student where stuid=1
查询
1、查询所有信息
select * from student
2、查询表中的行数
select count(*) from student
3、降序排列
select * from student order by stuid desc
升序排列
select * from student order by stuid asc
4、分组
select count(*)from student group by stuname