主要原因是，最近在MacBook上折腾我之前的CAI框架，要展示给客户看项目，所以MacBook相对方便一些，穷人没有其他的笔记本（o(╥﹏╥)o）

其实也是反复试网上的东西，测出来的。

思路首先先删除之前的mysql，然后在安装。

不得不说homebrew是一个好动西，但是要穿墙速度才会快一些，我家小管道，勉勉强强吧。

先卸载mysql
sudo rm /usr/local/mysql  
sudo rm -rf /usr/local/mysql*  
sudo rm -rf /Library/StartupItems/MySQLCOM  
sudo rm -rf /Library/PreferencePanes/My*  
vim /etc/hostconfig    

sudo rm /usr/local/mysql  
sudo rm -rf /usr/local/mysql*  
sudo rm -rf /Library/StartupItems/MySQLCOM  
sudo rm -rf /Library/PreferencePanes/My*  
vim /etc/hostconfig    

都执行一遍基本上就卸载完毕了

然后就是更新和安装了

安装Homebrew，详细步骤参见Homebrew官网。
brew doctor确认brew在正常工作。
brew update更新包。
brew install mysql 安装mysql。

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

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
// 这里提示选一个密码强度等级
Please enter 0 = LOW, 1 = MEDIUM and 2 = STRONG: 1
Please set the password for root here.
// 然后按照所选的密码强度要求设定密码
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
 ... Failed! Error: Your password does not satisfy the current policy requirements

New password:

Re-enter new password:

Estimated strength of the password: 100
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.
// 这里删除默认无密码用户
Remove anonymous users? (Press y|Y for Yes, any other key for No) : y
Success.


Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.
// 禁止远程root登录，我选的是不禁止。因为我的mac上的数据库不会放到公网上，也不会存什么敏感数据
Disallow root login remotely? (Press y|Y for Yes, any other key for No) : no

 ... 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.

// 这里删除默认自带的test数据库
Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y
 - 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!

mysql要启动，才能使用mysql_secure_installation

mysql.server start就是启动命令，另外默认不是自启动的，需要开机启动的，可以自行百度。

就到这里吧，我用这个方法完美解决了我的需求。