MySQL 5.7遗忘root密码重置记录

摘要:MySQL 5.7设置root密码方法update mysql.user set authentication_string=PASSWORD('****') where user='root' and host='localhost';

操作系统：

[root@localhost ~]# cat /etc/redhat-release

CentOS Linux release 7.1.1503

MysQL版本5.7

mysql> select version();

+-----------+

| version()    |

+-----------+

| 5.7.9        |

+-----------+

1 row in set (0.00 sec)

安装MySQL的yum repo源：

[root@localhost ~]# rpm -ivh http://repo.mysql.com//mysql57-community-release-el7-7.noarch.rpm

安装MySQL

[root@localhost ~]# yum -y install mysql-community-server mysql-community-client

修改mysql 配置文件跳过密码验证

[root@localhost ~]# vim /etc/my.cnf

[mysqld]

skip-grant-tables

skip-networking

重启MySQL：

[root@localhost ~]# systemctl mysqld restart

匿名登录MySQL设置root密码：

[root@localhost ~]# mysql -uroot -p

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 2

Server version: 5.7.9 MySQL Community Server (GPL)

Copyright (c) 2000, 2015, 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> update mysql.user set PASSWORD=PASSWORD('test') where user='root' and host='localhost';

ERROR 1054 (42S22): Unknown column 'PASSWORD' in 'field list'
提醒：从5.7开始使用authentication_string不再使用password字段存放密码所以提示出错。

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'test' ;

ERROR 1131 (42000): You are using MySQL as an anonymous user and anonymous users are not allowed to change passwords

查看mysql.user表密码字段：
mysql> desc mysql.user;

mysql> update mysql.user set authentication_string=PASSWORD('test') where user='root' and host='localhost';

Query OK, 1 row affected, 1 warning (0.07 sec)

Rows matched: 1  Changed: 1  Warnings: 1

mysql> flush privileges;

Query OK, 0 rows affected (0.06 sec)

mysql> select host,user,password from mysql.user;

mysql> exit;

Bye

取消跳过密码认证：

[root@localhost ~]# vim /etc/my.cnf

[mysqld]

#skip-grant-tables

#skip-networking

重启MySQL：

[root@localhost ~]# systemctl mysqld restart

必须使用alter user重置密码：

mysql> show databases;

ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.

重新设置新密码：

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '********'

ERROR 1820 (HY000): You must SET PASSWORD before executing this statement

密码需要复杂度要求：

mysql> SHOW VARIABLES LIKE 'validate_password%';

+--------------------------------------+--------+

| Variable_name                          | Value  |

+--------------------------------------+--------+

| validate_password_dictionary_file|         |

| validate_password_length           | 8      |

| validate_password_mixed_case_count| 1       |

| validate_password_number_count| 1       |

| validate_password_policy             | MEDIUM |

| validate_password_special_char_count| 1       |

+--------------------------------------+--------+

6 rows in set (0.00 sec)

mysql> set password=password('xxxx');
Query OK, 0 rows affected (0.00 sec)