基本操作

• 连接数据库，enter，输入密码

 mysql -u root -p

• 查看所有数据库

show databases;

• 使用某个数据库

use brave

• 查看数据库中的表

show tables

• 创建表

CREATE TABLE users  (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(20) NOT NULL,
  `password` varchar(20) NOT NULL,
  `nickname` varchar(10) NOT NULL,
  PRIMARY KEY (`id`)
);

• 新增数据

INSERT INTO users (username,password,nickname) VALUES('JonSnow','123456','雪诺');

• 查看数据

SELECT * FROM users;

• 查看部分字段

SELECT username,nickname FROM users;

• 删除数据

DELETE FROM users WHERE username='张三';

• 精确查询

SELECT username,nickname FROM users WHERE username='Cercei' and password=123456

• 更新数据

UPDATE blogs SET content='念念不忘，必有回响' WHERE id=1

• 排序

SELECT * FROM blogs ORDER BY id DESC;

• 数量统计

SELECT COUNT(*) as count from blogs;//不要使用*
SELECT COUNT(id) as count from blogs;

• 分页

SELECT * FROM users ORDER BY id DESC LIMIT 2 OFFSET 2;