CentOS7修改MySQL8的root账户密码

MySQL5.7.9后废弃了password字段和password()函数，authentication_string字段表示用户密码，authentication_string字段只能是mysql加密后的41位字符串密码。修改密码的方式较之前发生了改变，可按如下操作修改：

修改前先检查密码是否为空

• 密码不为空

mysql -u root -p  //登录mysql
use mysql;
update user set authentication_string='' where user='root';  //置空root账号密码
ALTER user 'root'@'localhost' IDENTIFIED BY 'rootpassword';  //修改密码为 rootpassword

• 密码为空
  直接修改密码

ALTER user 'root'@'localhost' IDENTIFIED BY 'rootpassword';

如何出现如下错误：

ERROR 1290 (HY000):The MYSQL server is running with the --skip-grant-tables option so it cannot execute this statement

需要执行：

GRANT ALL PRIVILEGES ON *.* TO IDENTIFIED BY '123' WITH GRANT OPTION;
flush privileges;

最后再修改密码：

ALTER user 'root'@'localhost' IDENTIFIED BY 'rootpassword';