参考文档：
https://mysql.net.cn/doc/refman/8.0/en/mysql-config-editor.html

OS上分别有2套库，设置后，通过不使用密码来登录，类似postgres的.pgpass文件 

-- 执行一下命令，会要求提示输入密码 

mysql_config_editor set --login-path=3306 --user=root  --host=127.0.0.1 --port=3306 --password
mysql_config_editor set --login-path=3307 --user=root  --host=127.0.0.1 --port=3307 --password

-- 产生的.mylogin.cnf文件，这是一个隐藏文件 ，而且不是文本格式的，所以打开会是乱码

[root@redhat762100 ~]# more .mylogin.cnf
�ԋu����>���J

--通过print打印出分组3306，分组3307，以及所有的内容 

[root@redhat762100 ~]# mysql_config_editor print --login-path=3306
[3306]
user = root
password = *****
host = 127.0.0.1
port = 3306
[root@redhat762100 ~]# mysql_config_editor print --login-path=3307
[3307]
user = root
password = *****
host = 127.0.0.1
port = 3307
[root@redhat762100 ~]#[root@redhat762100 ~]# mysql_config_editor print --all
[3306]
user = root
password = *****
host = 127.0.0.1
port = 3306
[3307]
user = root
password = *****
host = 127.0.0.1
port = 3307
[root@redhat762100 ~]#

-- 通过免密码登录到3306库

[root@redhat762100 ~]# mysql --login-path=3306
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 30
Server version: 5.7.25-log MySQL Community Server (GPL)Copyright (c) 2000, 2019, 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.root@db 15:27:  [(none)]>

-- 通过免密码登录到3307库 

[root@redhat762100 ~]# mysql --login-path=3307
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 12
Server version: 5.7.25-log MySQL Community Server (GPL)Copyright (c) 2000, 2019, 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.root@db 15:27:  [(none)]>

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