默认用户是root，密码为空。当安装WordPress和moodle时，数据库密码不允许空。可做如下处理：>mysql -u root -p ;
>use mysql;;
> insert into user(host,user) values(“%”‘,”cnliutz');
mysql>grant all privileges on *.* to 'root'@'%' identified by '2234‘
mysql>GRANT ALL PRIVILEGES ON *.* TO ‘root’@’%’ IDENTIFIED BY ‘2345’ WITH GRANT OPTION;
mysql>flush privileges;
cnliutz可远程访问，*.*代表所有数据库，2234是密码，%代表远程，也可以是localhost。
myql 8.0
>use mysql:
>alter user ‘root’@’localhost’ identified with mysql_native_password by “galaxy”;
create new user:
>create user cnliutz identified by “galaxy”;
>grant all privileges on . to ‘cnliutz’@’%’ ;
>flush privileges;