I forgot password, use this into the mysql
Mysqld, console, skip - grant - tables - Shared - memory

Then use the following change passwords, modify success, but not password encryption, is clear,
Update user set authentication_string='Js123456 where user=' root ';

Clear text passwords, mysql -u root -p, go to login, have been submitted to the ERROR 1045 ERROR, check the baidu, said the password to the password using encryption function ()
Then use the following this statement to modify the password,
Update the user set authentication_string=password (' 123456 ') where the user='root';

Always an error
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 '(' Js123456) where the user=' root 'at line 1

Version is 8.0.16, who is a great god can help me? Thank you for the