create database test;
use test;
create table student (
id int,
name varchar(255),
address varchar(255),
city varchar(255)
);
alter table student add age int;
INSERT INTO student VALUES (1, '刘一', '郑十', '河南','24');
INSERT INTO student VALUES (2, '陈二', '李四', '安徽','24');
INSERT INTO student VALUES (3, '张三', '白娘', '杭州','22');
INSERT into student(name) VALUES('hh');
INSERT into student(name,age) VALUES('ee',11);
update student set age=11 where name=ee;
SELECT * FROM student;