</pre>
*https://dev.mysql.com/doc/refman/8.0/ja/resetting-permissions.html
<pre>
mysql> FLUSH PRIVILEGES;
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass';
</pre>
<pre>
ubuntu@ip-172-26-11-57:~$ mysql -u debian-sys-maint -p
mysql> set password for 'root'@'localhost' = 'NewPassword';
ERROR 4102 (HY000): SET PASSWORD has no significance for user 'root'@'localhost' as the authentication method used doesn't store authentication data in the MySQL server. Please consider using ALTER USER instead if you want to change authentication parameters.
</pre>
*以下で成功!
<pre>
mysql> ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password by 'NewPassword';
Query OK, 0 rows affected (0.01 sec)