详解mysql5.7密码忘记解决方法

env：

[root@centos7 ~]# uname -r
3.10.0-514.el7.x86_64
[root@centos7 ~]# cat /etc/redhat-release 
centos linux release 7.3.1611 (core) 
[root@centos7 ~]# rpm -qa mysql
[root@centos7 ~]# rpm -qa |grep mysql
mysql-community-common-5.7.26-1.el7.x86_64
mysql-community-client-5.7.26-1.el7.x86_64
mysql57-community-release-el7-11.noarch
mysql-community-server-5.7.26-1.el7.x86_64
mysql-community-libs-5.7.26-1.el7.x86_64
mysql-community-libs-compat-5.7.26-1.el7.x86_64

登陆时出错：

[root@centos7 ~]# mysql -u root -p
enter password: 
error 1045 (28000): access denied for user 'root'@'localhost' (using password: no)

密码忘记了（和刚安装后不知道密码一样）

网上有人说mysql的密码是空密码，其实在mysql5.7版本之后，密码不再是空密码了，

如果是刚安装的，可以在mysql的日志文件找到

grep 'temporary password' /var/log/mysqld.log

补充：如果找到mysql提供的密码，可以使用

mysqladmin -u root -p 'mysql提供的密码' password ‘自己的新密码' 

直接修改mysql的密码，但这种方法存在安全隐患，毕竟密码在命令行上显示了，不建议但不反对。

如果是忘记，修改如下：

1.修改 /etc/my.cnf,加入 skip-grant-tables;

[root@centos7 ~]# vim /etc/my.cnf

空白位置加入，并保存退出；

[mysqld]
     
skip-name-resolve
skip-grant-tables

[root@centos7 ~]# systemctl restart mysqld

2.空密码直接进入mysql；

[root@centos7 ~]# mysql -u root -p
enter password: (这里是空密码，直接回车)
welcome to the mysql monitor. commands end with ; or \g.
your mysql connection id is 2
server version: 5.7.26 mysql community server (gpl)
 
copyright (c) 2000, 2019, 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>

进入mysql库；

mysql> use mysql
reading table information for completion of table and column names
you can turn off this feature to get a quicker startup with -a
 
database changed
mysql>

这里的mysql并不是没变，数据库位置是变化的；

3.修改密码：update user set authentication_string=password('newpassword') where user='root';

mysql> update user set authentication_string=password('newpassword') where user='root';
query ok, 1 row affected, 1 warning (0.00 sec)
rows matched: 1 changed: 1 warnings: 1
 
mysql> 
mysql> flush privileges;
query ok, 0 rows affected (0.00 sec)
 
mysql>

4改回/etc/my.cnf

注释掉 ＃skip-grant-tables

[root@centos7 ~]# vim /etc/my.cnf

[mysqld]
     
skip-name-resolve
#skip-grant-tables

[root@centos7 ~]# systemctl restart mysqld

5.用新的密码再进入mysql；

[root@centos7 ~]# mysql -u root -p 
enter password: (之前演示为newpassword)
welcome to the mysql monitor. commands end with ; or \g.
your mysql connection id is 6
server version: 5.7.26
 
copyright (c) 2000, 2019, 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>

6.更改root密码，更改root密码： alter user 'root'@'localhost' identified by '密码';

修改用户密码；

alter user testuser identified by '123456';

修改当前登录用户

alter user user() identified by '123456';

mysql> alter user user() identified by 'linuxpassword!@#';
error 1819 (hy000): your password does not satisfy the current policy requirements
mysql> alter user user() identified by 'linux123password!@#';
query ok, 0 rows affected (0.00 sec)
 
mysql> 

可以看出，密码的复杂度有了很大的要求；

7.修改完成后就可以继续操作mysql了

mysql> show databases;
+--------------------+
| database      |
+--------------------+
| information_schema |
| mysql       |
| performance_schema |
| sys        |
+--------------------+
4 rows in set (0.00 sec)
 
mysql> exit
bye

以上所述是小编给大家介绍的mysql5.7密码忘记解决方法详解整合，希望对大家有所帮助