mysql常用

1、创建数据库

CREATE DATABASE dbname DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;

2、创建用户

CREATE USER 'username'@'localhost' IDENTIFIED BY 'password';

3、授权数据库

GRANT ALL PRIVILEGES ON dbname.* TO 'username'@'localhost';

刷新权限：FLUSH PRIVILEGES;

4、修改密码

ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '123456';

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mysql -u username -p

常用命令：

show databases;

use database_name;

show tables;

desc table_name;

truncate table xxx;   // 清空表数据，清空后自增字段从初始值开始，delete删除或清空数据，自增字段不会恢复初始值

alter table xxx add ...   //增加字段

alter table xxx modify [column_name ...]  //修改字段

alter table xxx change [column_name] [column_name ...]  //修改字段，可修改字段名

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mac 启动mysql :   /usr/local/mysql/support-files/mysql.server start