homebrew模式下安装的mysql忘记密码

➜  ~ cd /usr/local/Cellar/mysql/8.0.12/bin
➜  bin ./mysql.server stop
 ERROR! MySQL server PID file could not be found!
➜  bin ./mysqld_safe --skip-grant-tables &
[1] 3193
➜  bin 2019-05-06T02:34:49.6NZ mysqld_safe Logging to '/usr/local/var/mysql/ufohackerdeMacBook-Pro.local.err'.
2019-05-06T02:34:49.6NZ mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql

zsh: you have running jobs.
➜  bin mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 8.0.12 Homebrew

Copyright (c) 2000, 2018, 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> use mysql
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.03 sec)

mysql> exit;
Bye
➜  bin ./mysql.server stop
Shutting down MySQL
...2019-05-06T02:36:59.6NZ mysqld_safe mysqld from pid file /usr/local/var/mysql/ufohackerdeMacBook-Pro.local.pid ended
[1]  + 3193 done       ./mysqld_safe --skip-grant-tables
 SUCCESS!
➜  bin ./mysql.server start
Starting MySQL
.. SUCCESS!
➜  bin

命令详解:
# 进入mysql安装路径 /usr/local/Cellar/mysql/8.0.11/bin （每个人可能不一样）
cd /usr/local/Cellar/mysql/8.0.11/bin
# 暂停mysql服务
./mysql.server stop
# 安全模式启动mysql
./mysqld_safe --skip-grant-tables &
# 进入mysql交互模式
mysql

use mysql
flush privileges;
ALTER USER 'root'@'localhost' IDENTIFIED BY '新密码';

# 注意：重启mysql
./mysql.server stop
./mysql.server start