任务一 更改root密码

简略步骤

1. 更改环境变量
   修改/etc/profile文件，文件尾添加mysql的绝对路径，修改环境变量

   //修改配置文件
   # vim /etc/proflie
   //在文件的最下面添加mysql的绝对路径
   export PATH=$PATH:/usr/local/mysql/bin/

2. 创建MySQL密码
   使用命令mysqladmin -uroot password ‘bai’为root用户创建初始密码 ```powershell [root@bai mysql]# mysqladmin -uroot password ‘bai’ Warning: Using a password on the command line interface can be insecure. //注释：可以忽略warning内容，指的是明码输入屏幕不安全。 //使用命令mysql -uroot -pbai，就可以完成初始密码登录 [root@bai mysql]# mysql -uroot -pbai 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 9 Server version: 5.6.47 MySQL Community Server (GPL)

Copyright (c) 2000, 2020, 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. 密码重置<br />修改配置文件/etc/my.cnf，在mysqld配置段，增加字段skip-grant。
```powershell
//修改MySQL配置文件
[root@bai mysql]# vim /etc/my.cnf
//在[mysqld]下面加
skip-grant
//修改完成后，重启MySQL服务
[root@bai mysql]# /etc/init.d/mysqld restart
Shutting down MySQL.. SUCCESS! 
Starting MySQL. SUCCESS! 
使用命令登入MySQL（修改的配置段，是完成忽略授权的操作，可以直接登入，无需输入用户名密码），切换到MySQL库，对user表进行更新操作.
//登录无需密码
[root@bai mysql]# mysql -uroot
//切换库
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
//切换完成
Database changed
//修改密码
mysql> update user set password=password('bai123') where user='root';
Query OK, 4 rows affected (0.00 sec)
Rows matched: 4  Changed: 4  Warnings: 0
mysql> quit
Bye
主要：//修改完成后，确认新密码登录有效。把/etc/my.cnf改回原有状态，并重启MySQL服务。
[root@bai mysql]# vim /etc/my.cnf
[root@bai mysql]# 
[root@bai mysql]# 
[root@bai mysql]# 
[root@bai mysql]# /etc/init.d/mysqld restart
Shutting down MySQL.. SUCCESS! 
Starting MySQL. SUCCESS! 
[root@bai mysql]# mysql -uroot -p'bai123'
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 3
Server version: 5.6.47 MySQL Community Server (GPL)
Copyright (c) 2000, 2020, 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> 
//完成