报错信息:
mysql> mysqladmin -uroot -p123456 password 654321;
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 'mysqladmin -uroot -p123456 password 654321' at line 1
mysql> set password for root@localhost = password('654321');
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 'password('654321')' at line 1
报错原因：
新版本MySQL（8.0以上）不支持使用mysqladmin -uroot -p123456 password 654321;或“set password for root@localhost = password('654321');”来修改密码。
解决方法：
alter user'root'@'localhost' identified by '新密码';- 或
alter user'root'@'localhost' identified with mysql_native_password by '新密码';