>mysql -u root -p
Enter password: ********
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Your MySQL connection id is 12
Server version: 5.7.18-log MySQL Community Server (GPL)

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mysql> use mysql;
Database changed
mysql > select User from user; #here is the query user command
 +-----------+
| User      |
+-----------+
| ******* |
| mysql.sys |
| root      |
+-----------+
3 rows in set (0.00 sec)

mysql > update user set password=password( " ******* " ) where user = " ******* " ; #Modify password error
ERROR 1054 (42S22): Unknown column 'password' in 'field list'
mysql> update mysql.user set authentication_string=password('*******') where user='*******';  #修改密码成功
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 1

mysql > flush privileges; #effective immediately
Query OK, 0 rows affected (0.00 sec)

mysql> quit
Bye

n >mysql -u *******- p #Log in as this user successfully.
Enter password: ********
…………………………
mysql>