#允许所有用户远程访问 设置用户名和密码
mysql> GRANT ALL PRIVILEGES ON *.* TO 'USERNAME'@'%' IDENTIFIED BY 'PASSWORD' WITH GRANT OPTION;
#允许单个ip 设置用户名和密码
mysql> GRANT ALL PRIVILEGES ON *.* TO 'USERNAME'@'1.2.3.4' IDENTIFIED BY 'PASSWORD' WITH GRANT OPTION;
#操作完成后刷新
mysql> FLUSH PRIVILEGES;

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