设置mysqlroot密码

1、首次安装 root初始密码为空，注意就是没有密码，直接敲回车即可进入

注：在centos7下安装mysql5.6初次密码并不为空，而是生成了一个随机的密码。

A RANDOM PASSWORD HAS BEEN SET FOR THE MySQL root USER !

You will find that password in '/root/.mysql_secret'.

D:\wamp\bin\mysql\mysql5.6.17\bin>mysql -uroot -p

Enter password: [直接回车]

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

Your MySQL connection id is 7

Server version: 5.6.17 MySQL Community Server (GPL)

Copyright (c) 2000, 2014,Oracleand/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>

2、修改root密码的几种方法：

1） 用SET PASSWORD命令

首先登录MySQL。

格式：mysql> set password for 用户名@localhost = password('新密码');

例如：

mysql>set password for root@localhost = password('root');

Query OK, 0 rows affected (0.00 sec)

mysql>quit

Bye

D:\wamp\bin\mysql\mysql5.6.17\bin>mysql -uroot -proot

Warning: Using a password on the command line interface can be insecure.

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

Your MySQL connection id is 8

Server version: 5.6.17 MySQL Community Server (GPL)

Copyright (c) 2000, 2014, 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>

2）用mysqladmin

格式：mysqladmin -u用户名 -p旧密码 password 新密码

例如：

D:\wamp\bin\mysql\mysql5.6.17\bin>mysqladmin -uroot -proot password root123

Warning: Using a password on the command line interface can be insecure.

D:\wamp\bin\mysql\mysql5.6.17\bin>mysql -uroot -proot123

Warning: Using a password on the command line interface can be insecure.

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

Your MySQL connection id is 10

Server version: 5.6.17 MySQL Community Server (GPL)

Copyright (c) 2000, 2014, 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>

3）用UPDATE直接编辑user表

首先登录MySQL。

mysql> use mysql;

mysql> update user set password=password('root') where user='root' and host='localhost';

mysql> flush privileges;

--注意一定要flush privileges;

mysql 新设置用户或更改密码后需用flush privileges刷新MySQL的系统权限相关表，否则会出现拒绝访问，还有一种方法，就是重新启动mysql服务器，来使新设置生效。

4）在忘记root密码的时候，可以这样。

以windows为例：

1. 关闭正在运行的MySQL服务。

2. 打开DOS窗口，转到mysql\bin目录。

3. 输入mysqld --skip-grant-tables 回车。--skip-grant-tables 的意思是启动MySQL服务的时候跳过权限表认证。

4. 再开一个DOS窗口（因为刚才那个DOS窗口已经不能动了），转到mysql\bin目录。

5. 输入mysql回车，如果成功，将出现MySQL提示符 >。

6. 连接权限数据库： use mysql; 。

6. 改密码：update user set password=password('root123') where user='root';（别忘了最后加分号） 。

7. 刷新权限（必须步骤）：flush privileges;

8. 退出quit当前cmd，并且关闭2中的DOS窗口

9. 使用用户名root，新密码root123在4中DOS窗口登录。