1. 数据库初始化：
old : /usr/local/mysql/scripts/mysql_install_db --datadir=/usr/local/mysql/data/ --basedir=/usr/local/mysql --user=mysql
new : /usr/local/mysql/bin/mysqld --initialize --datadir=/usr/local/mysql/data/ --basedir=/usr/local/mysql --user=mysql
2. 修改或设置用户密码：
old : UPDATE user SET password=PASSWORD('123456') WHERE user='root';
new : UPDATE user SET authentication_string=PASSWORD('123456') WHERE user='root';
3. 第一次修改密码：
SET PASSWORD = PASSWORD('123456');
4. 外网访问：
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY '123456' WITH GRANT OPTION;
flush privileges