有些基础的语句很久没用会生疏，所以写个例子把所有的基础语句都写一遍，以便加深记忆。

drop table  if EXISTS stu;
create table stu(
name varchar(32),
age int,
stuid int,
idnum int,
sex varchar(30),
PRIMARY KEY(idnum),
check (sex in('男','女'))
)CHARSET=utf8; 
insert into stu values('tom',12,2010,123,'男');
insert into stu (name,age,stuid,idnum,sex) values('wilson',13,3465,676,'女');
update stu set age=15 where name='tom' or name='wilson';
SELECT name,age from stu  WHERE age BETWEEN 0 and 20 order by name asc;
DELETE from stu where name='tom';
select * from stu where age BETWEEN 0 and 20 order by name desc;

用的是mysq front 很好用的工具，推荐给大家！