1. 安裝Homebrew，詳細步驟參見Homebrew官網。
2. brew doctor確認brew在正常工作。
3. brew update更新包。
4. brew install mysql 安裝mysql。log如下：

   ==> Installing dependencies for mysql: openssl
   ==> Installing mysql dependency: openssl
   ==> Downloading https://homebrew.bintray.com/bottles/openssl-1.0.2l.sierra.bottle.tar.gz
   ######################################################################## 100.0%
   ==> Pouring openssl-1.0.2l.sierra.bottle.tar.gz
   ==> Using the sandbox
   ==> Caveats
   A CA file has been bootstrapped using certificates from the SystemRoots
   keychain. To add additional certificates (e.g. the certificates added in
   the System keychain), place .pem files in
   /usr/local/etc/openssl/certs

   and run
   /usr/local/opt/openssl/bin/c_rehash

   This formula is keg-only, which means it was not symlinked into /usr/local,
   because Apple has deprecated use of OpenSSL in favor of its own TLS and crypto libraries.

   If you need to have this software first in your PATH run:
   echo ‘export PATH="/usr/local/opt/openssl/bin:$PATH"‘ >> ~/.bash_profile

   For compilers to find this software you may need to set:
   LDFLAGS: -L/usr/local/opt/openssl/lib
   CPPFLAGS: -I/usr/local/opt/openssl/include

   ==> Summary
   ?? /usr/local/Cellar/openssl/1.0.2l: 1,709 files, 12.2MB
   ==> Installing mysql
   ==> Downloading https://homebrew.bintray.com/bottles/mysql-5.7.18_1.sierra.bottle.tar.gz
   ######################################################################## 100.0%
   ==> Pouring mysql-5.7.18_1.sierra.bottle.tar.gz
   ==> /usr/local/Cellar/mysql/5.7.18_1/bin/mysqld --initialize-insecure --user=chenxu --basedir=/usr/local/Cellar/mysql/5.7.18_1 --datadir=/usr/local/var/mysq
   ==> 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/5.7.18_1: 321 files, 232.9MB

5. 後臺啟動服務：brew services start mysql
6. 前臺啟動服務：mysql.server start
7. 安裝後的mysql無root密碼，登錄mysql：mysql -u root -p

macbook install mysql