mysql> show variables like "%version%";
+-------------------------+------------------------------+
| Variable_name           | Value                        |
+-------------------------+------------------------------+
| innodb_version          | 5.7.13                       |
| protocol_version        | 10                           |
| slave_type_conversions  |                              |
| tls_version             | TLSv1,TLSv1.1                |
| version                 | 5.7.13                       |
| version_comment         | MySQL Community Server (GPL) |
| version_compile_machine | x86_64                       |
| version_compile_os      | Linux                        |
+-------------------------+------------------------------+
8 rows in set (0.01 sec)

mysql> update user set password=PASSWORD("XXXX") where user="root";
ERROR 1054 (42S22): Unknown column 'password' in 'field list'

mysql> use mysql;

mysql> show tables;

mysql> describe user;

update user set authentication_string=password('XXXX') where user='root';

mysql> SET PASSWORD FOR 'root' = PASSWORD('new_password');