alter user ‘root‘@’localhost’identified with mysql_native_password by ‘新密码’;

这行会报错，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 'mysql_native_password by 123456' at line 1

正确如下：

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123456';