create database kali;
use kali;
show tables;
create table students (
SNO varchar(10) primary key,
SNAME varchar(10) not null,
SEX varchar(2) check(sex in('男','女')),
AGE varchar(3)
);
insert into students values ('1','xiaoming','男','23');
insert into students values ('2','xiaoli','女','43');
insert into students values ('3','xiaohua','男','34');
insert into students values ('4','xiaoxin','男','6');
insert into students values ('5','xiaoma','女','77');
insert into students values ('6','xiaowang','男','54');