Mysql版本：5.7.17 系统环境：Center OS

初始化Root密码–CenterOS

获取初始Root密码

grep 'temporary password' /var/log/mysqld.log

重置Root密码

1.Stop mysql: systemctl stop mysqld

2.Set the mySQL environment option

systemctl set-environment MYSQLD_OPTS="--skip-grant-tables"

3.Start mysql usig the options you just set systemctl start mysqld 4.Login as root mysql -u root 5.Update the root user password with these mysql commands

mysql> UPDATE mysql.user SET authentication_string = PASSWORD('MyNewPassword')
    -> WHERE User = 'root' AND Host = 'localhost';
mysql> FLUSH PRIVILEGES;
mysql> quit

6.Stop mysql systemctl stop mysqld 7.Unset the mySQL envitroment option so it starts normally next time systemctl unset-environment MYSQLD_OPTS 8.Start mysql normally: systemctl start mysqld 7.Try to login using your new password: mysql -u root -p

开启远程登录–授权

语法1：授权用户访问所有数据库 GRANT ALL PRIVILEGES ON *.* TO 'username'@'%' IDENTIFIED BY 'password' WITH GRANT OPTION;

语法2：授权用户访问指定数据库 GRANT ALL PRIVILEGES ON database_name.* TO 'username'@'%' IDENTIFIED BY 'password' WITH GRANT OPTION;

语法3：授权用户访问指定数据库–精简 GRANT ALL PRIVILEGES ON database_name.* TO 'username'@'%';

问题：语法1和2由于涉及到password，5.7.6以后会出现如下报错 ERROR 1819 (HY000): Your password does not satisfy the current policy requirements 解决方法： SET GLOBAL validate_password_policy='LOW';

最后记得：刷新权限 FLUSH PRIVILEGES;

授权清除方法

1.To list users: select user,host from mysql.user;

2.To show privileges: show grants for 'user'@'host';

3.To change privileges, first revoke. Such as: revoke all privileges on *.* from 'user'@'host';

4.Then grant the appropriate privileges as desired: grant SELECT,INSERT,UPDATE,DELETE ON db.* TO 'user'@'host';

5.Finally, flush: flush privileges;

参考链接1：How to Grant All Privileges on a Database in MySQL 参考链接2：How To Create a New User and Grant Permissions in MySQL 参考链接3：Mysql初始化root密码和允许远程访问