Brew 卸载MySql以及安装Mysql

卸载：

1.brew remove mysql

2.brew cleanup

3.launchctl unload -w ~/Library/LaunchAgents/com.mysql.mysqld.plist

4.rm ~/Library/LaunchAgents/com.mysql.mysqld.plist

5.sudo rm -rf /usr/local/var/mysql

安装

1. 使用homebrew一键安装相应的包，因为homebrew会检测最新的版本，所以下载的mysql版本是5.7.*版本
   最近安装的时候最新版本更新到8.x版本，

   关于homebrew的安装，链接

   ? /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
   

   搜索一下mysql版本：

   brew search mysql
   
   
   ==> Formulae
   automysqlbackup       mysql-cluster         mysql-search-replace  mysql@5.7
   mysql                 mysql-connector-c     mysql-utilities       mysqltuner
   mysql++               mysql-connector-c++   mysql@5.5
   mysql-client          mysql-sandbox         mysql@5.6
   
   
   ==> Casks
   homebrew/cask/mysql-connector-python         homebrew/cask/navicat-for-mysql
   homebrew/cask/mysql-shell                    homebrew/cask/sqlpro-for-mysql
   homebrew/cask/mysql-utilities
   

   安装mysql:

   ? brew install mysql@5.7
   ? ln -sfv /usr/local/opt/mysql@5.7/*.plist ~/Library/LaunchAgents
   ? mysql.server start
   

   如果mysql.server start说zsh: command not found: mysql.server的话，配置一下环境变量，如果是卸载重新切换版本的话brew link mysql@5.7

   上面的第二步骤是设置开机启动

   登录

   ? mysql -uroot
   
   
   show databases;
   +--------------------+
   | Database           |
   +--------------------+
   | information_schema |
   | mysql              |
   | performance_schema |
   | sys                |
   +--------------------+
   4 rows in set (0.00 sec)
   

   修改root密码

   use mysql
   update user set authentication_string = password('root') where User='root';
   Query OK, 1 row affected, 1 warning (0.00 sec)
   Rows matched: 1  Changed: 1  Warnings: 1
   

   以前修改mysql密码字段是Password这个字段，但是mysql5.7没有这个字段而是使用了authentication_string替代

   mysql> flush privileges;
   Query OK, 0 rows affected (0.00 sec)
   

   如果操作过程中报下面的错误

   ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
   

   那么使用首先关闭mysql服务，然后以安全模式启动
   mysql.server start --skip-grant-tables

最后可以参考：https://blog.csdn.net/cheng649090216/article/details/79246333