本意向修改一个用户的密码，网上搜到的命令为如下
mysql> update user set password=password(“新密码”) where user=”用户名”;
执行后报错 ERROR 1054(42S22) Unknown column 'password' in ‘field list’
错误的原因是 5.7版本下的mysql数据库下已经没有password这个字段了，password字段改成了authentication_string
所以请使用一下命令：
>mysql -u root -p
Enter password: ********
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is
Server version: 5.7.-log MySQL Community Server (GPL) Copyright (c) , , Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> use mysql;
Database changed
mysql> select User from user; #此处为查询用户命令
+-----------+
| User |
+-----------+
| ******* |
| mysql.sys |
| root |
+-----------+
rows in set (0.00 sec) mysql> update user set password=password("*******") where user="*******"; #修改密码报错
ERROR (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, row affected, warning (0.00 sec)
Rows matched: Changed: Warnings: mysql> flush privileges; #立即生效
Query OK, rows affected (0.00 sec) mysql> quit
Bye n>mysql -u ******* -p #以该用户登录成功.
Enter password: ********
…………………………
mysql>