create database myhome;
CREATE DATABASE test;
use test;
CREATE TABLE student (
id int,
name varchar(255),
address varchar(255),
city varchar(25)
);
INSERT INTO student VALUES (1, '刘一', '郑十家隔壁', '河南');
INSERT INTO student VALUES (2, '陈二', '李四家隔壁', '安徽');
INSERT INTO student VALUES (3, '张三', '白娘子家隔壁', '杭州');
INSERT INTO student VALUES (4, '李四', '许仙家隔壁', '杭州');
INSERT INTO student VALUES (5, '王五', '李四家隔壁', '杭州');
INSERT INTO student VALUES (6, '赵六', '赵六家隔壁', '杭州');
INSERT INTO student VALUES (7, '孙七', '张三家隔壁', '杭州');
INSERT INTO student VALUES (8, '周八', '雷峰塔附近', '杭州');
INSERT INTO student VALUES (9, '吴九', '孙七家隔壁', '杭州');
INSERT INTO student VALUES (10, '郑十', '周八家隔壁', '杭州');
insert into student (id, name, address, city)
VALUES (
5, '五格', '许仙家楼下', '横店'
);
update student set address = '白蛇家隔壁'where id = 3;
select address from student where id = 5;
update student set city = '西湖' where id = 3;
SELECT * FROM student;
SELECT city, COUNT(*) AS student_count
FROM student
GROUP BY city;