cd /usr/local/mysql/bin

sudo su

sudo /usr/local/mysql/support-files/mysql.server stop

#

./mysqld_safe --skip-grant-tables &

## 新开一个窗口

cd /usr/local/mysql/bin

./mysql -u -root

## For MySQL older than MySQL 5.7 use:

## UPDATE mysql.user SET Password=PASSWORD('your-password') WHERE User='root';

## For MySQL 5.7+ use:

USE mysql;

UPDATE mysql.user SET authentication_string=PASSWORD("your-password") WHERE User='root';