Navicat连接远程主机（腾讯云服务器）的mysql失败，解决(为需要远程登录的用户赋予权限)

赋予所有用户远程连接的权限，重启mysql即可连接成功：
mysql> grant all privileges on . to 'root'@'%' identified by '密码';
提示 Query OK, 0 rows affected, 1 warning (0.00 sec), 说明成功.

systemctl start mysqld.service 启动
systemctl stop mysqld.service 停止
systemctl restart mysqld.service 重启