这个问题首先网上的都是using password :yes ,然后我发现我的是no ,但是目前我还没有发现有什么区别，等后续用的多了，再来update

解决方案：

vim /etc/my.cnf

添加

[mysqld]

skip-grant-tables

(因为我发现百度上的人都是自己就有mysqld ，本来我是直接follow 他们直接加了skip ，但是没有生效，于是另外加上了[mysqld])

 最后

[root@localhost ~]# systemctl restart mysqld.service  --> 重新启动mysql service 
[root@localhost ~]# mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 8.0.13 Source distribution

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.

mysql> exit;
Bye

mysql --ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)