MySQL初始化账户，或者修改root密码的命令:

ALTER USER 'root'@'localhost' IDENTIFIED BY 'root' PASSWORD EXPIRE NEVER; #修改加密规则 

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'root'; #更新一下用户的密码 

FLUSH PRIVILEGES; #刷新权限

--创建新的用户：

create user root@'%' identified WITH mysql_native_password BY 'root';

grant all privileges on *.* to root@'%' with grant option;

flush privileges;

--在MySQL8.0创建用户并授权的语句则不被支持：

mysql> grant all privileges on *.* to root@'%' identified by 'root' with grant option;

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'identified by 'root' with grant option' at line 1

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