インストール
$ brew update
$ brew install mysql
mysql 起動
（停止は $ mysql.server stop)
$ mysql.server start
Starting MySQL
. SUCCESS!
コンソールに接続
$ mysql -uroot
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.20 Homebrew
Copyright (c) 2000, 2017, 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>
パスワード設定
$ mysql_secure_installation
パスワードログイン
$ mysql -uroot -p