[Mac] Homebrew 安装 Mysql

安装 MySQL：brew install mysql

...
==> Caveats
We've installed your MySQL database without a root password. To secure it run:
    mysql_secure_installation

MySQL is configured to only allow connections from localhost by default

To connect run:
    mysql -uroot

To have launchd start mysql now and restart at login:
  brew services start mysql
Or, if you don't want/need a background service you can just run:
  mysql.server start
==> Summary
🍺  /usr/local/Cellar/mysql/5.7.20: 324 files, 233.7MB

根据提示，执行：mysql_secure_installation

Securing the MySQL server deployment.

Enter password for user root: 
Error: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)

报错，原因 MySQL 进程还没启动，启动 MySQL 服务：mysql.server start，再次执行：mysql_secure_installation

Securing the MySQL server deployment.

Connecting to MySQL using a blank password.

VALIDATE PASSWORD PLUGIN can be used to test passwords
and improve security. It checks the strength of password
and allows the users to set only those passwords which are
secure enough. Would you like to setup VALIDATE PASSWORD plugin?

Press y|Y for Yes, any other key for No: y // 是否配置验证密码插件

There are three levels of password validation policy:

LOW    Length >= 8
MEDIUM Length >= 8, numeric, mixed case, and special characters
STRONG Length >= 8, numeric, mixed case, special characters and dictionary                  file

Please enter 0 = LOW, 1 = MEDIUM and 2 = STRONG: 0 // 密码都已经最少8位了
Please set the password for root here.

New password: //

Re-enter new password: //

Estimated strength of the password: 50 
Do you wish to continue with the password provided?(Press y|Y for Yes, any other key for No) : y //
By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them. This is intended only for
testing, and to make the installation go a bit smoother.
You should remove them before moving into a production
environment.

Remove anonymous users? (Press y|Y for Yes, any other key for No) : y // 是否删除无密码用户
Success.


Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.

Disallow root login remotely? (Press y|Y for Yes, any other key for No) : n // 是否 禁止 root 远程登录

 ... skipping.
By default, MySQL comes with a database named 'test' that
anyone can access. This is also intended only for testing,
and should be removed before moving into a production
environment.


Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y // 是否删除 test 数据库
 - Dropping test database...
Success.

 - Removing privileges on test database...
Success.

Reloading the privilege tables will ensure that all changes
made so far will take effect immediately.

Reload privilege tables now? (Press y|Y for Yes, any other key for No) : y //
Success.

All done!