MySQL 修改用户密码及重置root密码
为数据库用户修改密码是DBA比较常见的工作之一。对于MySQL用户账户的密码修改,有几种不同的方式,推荐的方式使用加密函数来修改
为数据库用户修改密码是DBA比较常见的工作之一。对于MySQL用户账户的密码修改,,有几种不同的方式,推荐的方式使用加密函数来修改密码。本文主要描述了通过几种不同的方式来修改用户密码以及mysql root账户密码丢失(重置root密码)的处理方法。
1、密码修改的几种方法
a、可以在创建用户的时候指定密码,以及直接使用grant创建用户的时候指定密码。
对于已经存在的用户直接使用grant方式也可以修改密码
如下:
--演示版本
root@localhost[(none)]> show variables like 'version%';
+-------------------------+------------------------------+
| Variable_name | Value |
+-------------------------+------------------------------+
| version | 5.5.37 |
| version_comment | MySQL Community Server (GPL) |
| version_compile_machine | x86_64 |
| version_compile_os | Linux |
+-------------------------+------------------------------+
--下面我们使用grant方式创建一个新帐户fred,并设定密码
root@localhost[(none)]> grant usage on *.* to 'fred'@'localhost' identified by 'fred';
Query OK, 0 rows affected (0.00 sec)
--查看刚刚创建的账户
root@localhost[(none)]> select host,user,password from mysql.user where user='fred';
+-----------+------+-------------------------------------------+
| host | user | password |
+-----------+------+-------------------------------------------+
| localhost | fred | *6C69D17939B2C1D04E17A96F9B29B284832979B7 |
+-----------+------+-------------------------------------------+
--下面可以成功登陆mysql
SZDB:~ # mysql -ufred -pfred
fred@localhost[(none)]>
b、使用set password方式来修改账户密码
--下面我们使用set password方式来设定密码
root@localhost[(none)]> set password for 'fred'@'localhost'=password('passwd');
Query OK, 0 rows affected (0.00 sec)
root@localhost[(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec)
--再次登陆时,之前的密码已经失效,无法登陆
SZDB:~ # mysql -ufred -pfred
ERROR 1045 (28000): Access denied for user 'fred'@'localhost' (using password: YES)
--下面使用新密码登陆成功
SZDB:~ # mysql -ufred -ppasswd
fred@localhost[(none)]>
--检索数据库是否存在linuxidc用户,如下密码为null
root@localhost[(none)]> select host,user,password from mysql.user where user='linuxidc';
+-----------+------+----------+
| host | user | password |
+-----------+------+----------+
| localhost | linuxidc | |
+-----------+------+----------+
c、加密方式更新系统表user的password列
--我们尝试直接更新密码列(不使用加密函数方式)
root@localhost[(none)]> update mysql.user set password='linuxidc' where user='linuxidc';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
--由于直接使用明文,因此系统表user列password显示为明文
root@localhost[(none)]> select host,user,password from mysql.user where user='linuxidc';
+-----------+------+----------+
| host | user | password |
+-----------+------+----------+
| localhost | linuxidc | jack |
+-----------+------+----------+
--Author : Leshami
--Blog :
root@localhost[(none)]> flush privileges;
Query OK, 0 rows affected (0.02 sec)
--此时无法登陆
SZDB:~ # mysql -ulinuxidc -pjack -h localhost
ERROR 1045 (28000): Access denied for user 'linuxidc'@'localhost' (using password: YES)
--下面我们通过set方式来修改linuxidc的密码,提示找不到linuxidc用户
root@localhost[(none)]> set password for 'linuxidc'@'localhost'=password('linuxidc');
ERROR 1133 (42000): Can't find any matching row in the user table
--我们切换到mysql数据库下尝试,
root@localhost[(none)]> use mysql
root@localhost[mysql]> set password for 'linuxidc'@'localhost'=password('passwd'); --在mysql数据库下依旧无法更新用户linuxidc的密码
ERROR 1133 (42000): Can't find any matching row in the user table
--下面我们尝试用password函数方式来更新password列
root@localhost[mysql]> update user set password=password('passwd') where user='linuxidc'; --此方式更新成功
Query OK, 1 row affected (0.04 sec)
Rows matched: 1 Changed: 1 Warnings: 0
root@localhost[mysql]> select host,user,password from user where user='linuxidc'; --可以看到密码已经变成了密文
+-----------+------+-------------------------------------------+
| host | user | password |
+-----------+------+-------------------------------------------+
| localhost | linuxidc | *59C70DA2F3E3A5BDF46B68F5C8B8F25762BCCEF0 |
+-----------+------+-------------------------------------------+
root@localhost[mysql]> flush privileges;
Query OK, 0 rows affected (0.00 sec)
--此时登陆成功
robin@SZDB:~> mysql -ulinuxidc -ppasswd
linuxidc@localhost[(none)]>
--------------------------------------分割线 --------------------------------------
Ubuntu 14.04下安装MySQL
《MySQL权威指南(原书第2版)》清晰中文扫描版 PDF
Ubuntu 14.04 LTS 安装 LNMP Nginx\PHP5 (PHP-FPM)\MySQL
Ubuntu 14.04下搭建MySQL主从服务器
Ubuntu 12.04 LTS 构建高可用分布式 MySQL 集群
Ubuntu 12.04下源代码安装MySQL5.6以及Python-MySQLdb
MySQL-5.5.38通用二进制安装
--------------------------------------分割线 --------------------------------------
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