1. 安装

教学视频：https://www.bilibili.com/video/BV1iq4y1u7vj

mysql官网地址：https://dev.mysql.com/downloads/mysql/ 找到适合版本的rpm文件下载
查看当前Linux系统版本信息：https://cloud.tencent.com/developer/article/1721171

  1. #查看当前是否有安装过MySQL
  2. [root@localhost ~]# rpm -qa | grep -i mysql
  4. #下载好的mysql服务daunt和客户端
  5. [root@localhost mysql]# ll
  6. 总用量 515936
  7. -rw-r--r--. 1 root root  55199948 1月  22 19:12 mysql-community-client-8.0.28-1.el7.x86_64.rpm
  8. -rw-r--r--. 1 root root 473116268 1月  22 19:12 mysql-community-server-8.0.28-1.el7.x86_64.rpm
  10. [root@localhost mysql]# rpm -ivh mysql-community-server-8.0.28-1.el7.x86_64.rpm 
  11. 警告：mysql-community-server-8.0.28-1.el7.x86_64.rpm: 头V4 RSA/SHA256 Signature, 密钥 ID 3a79bd29: NOKEY
  12. 错误：依赖检测失败：
  13.     mysql-community-client(x86-64) >= 8.0.11 被 mysql-community-server-8.0.28-1.el7.x86_64 需要
  14.     mysql-community-common(x86-64) = 8.0.28-1.el7 被 mysql-community-server-8.0.28-1.el7.x86_64 需要
  15.     mysql-community-icu-data-files = 8.0.28-1.el7 被 mysql-community-server-8.0.28-1.el7.x86_64 需要
  16.     net-tools 被 mysql-community-server-8.0.28-1.el7.x86_64 需要
  17. [root@localhost mysql]#

安装出错，需要的依赖并没有被安装
解决方案：下载bundle包，按顺序安装
https://blog.csdn.net/weixin_33881140/article/details/92619195（bundle包和其他包的区别）
https://zhuanlan.zhihu.com/p/143599392（mysql的bundle包安装）
https://blog.csdn.net/qq_35155680/article/details/115267192（安装问题）

安装完成后，查看MySQL安装时创建的MySQL用户和MySQL组

  1. [root@localhost mysql]# id mysql
  2. uid=27(mysql) gid=27(mysql) 组=27(mysql)
  3. [root@localhost mysql]# cat /etc/group | grep mysql
  4. mysql:x:27:
  5. [root@localhost mysql]# cat /etc/passwd | grep mysql
  6. mysql:x:27:27:MySQL Server:/var/lib/mysql:/bin/false
  7. [root@localhost mysql]# 
  10. #启动MySQL
  11. [root@localhost mysql]# service mysqld start
  12. Redirecting to /bin/systemctl start mysqld.service
  13. [root@localhost mysql]# ps -ef | grep mysql
  14. mysql      1874      1  7 22:24 ?        00:00:01 /usr/sbin/mysqld
  15. root       1919   1332  0 22:24 pts/0    00:00:00 grep --color=auto mysql
  16. [root@localhost mysql]# 
  18. #设置MySQL开机自启
  19. [root@localhost mysql]# systemctl enable mysqld

查看MySQL安装后的初始密码：
https://www.jianshu.com/p/f2da46fcee07（查看密码）
https://blog.csdn.net/ayychiguoguo/article/details/120370686（修改密码）
https://blog.csdn.net/muziljx/article/details/81541896（配置密码过期时间）

查看密码

  1. 找到mysql的配置文件my.cnf（/etc/my.cnf），查看日志文件所在路径
  2. 在日志中搜索关键字password，即可得到MySQL的初始密码

MySQL初始密码查看.png

  1. #修改密码校验
  3. mysql> SHOW VARIABLES LIKE 'validate_password%';
  4. +--------------------------------------+-------+
  5. | Variable_name                        | Value |
  6. +--------------------------------------+-------+
  7. | validate_password.check_user_name    | ON    |
  8. | validate_password.dictionary_file    |       |
  9. | validate_password.length             | 8     |
  10. | validate_password.mixed_case_count   | 1     |
  11. | validate_password.number_count       | 1     |
  12. | validate_password.policy             | LOW   |
  13. | validate_password.special_char_count | 1     |
  14. +--------------------------------------+-------+
  15. 7 rows in set (0.01 sec)
  17. mysql> set global validate_password.length=1;
  18. Query OK, 0 rows affected (0.00 sec)
  20. mysql> set global validate_password.special_char_count=0;
  21. Query OK, 0 rows affected (0.00 sec)
  23. mysql> alter user 'root'@'localhost' identified by '123456';
  24. Query OK, 0 rows affected (0.00 sec)
  26. mysql>

2. 卸载

https://blog.csdn.net/Chihider/article/details/119842559

  1. # 1.检查MySQL是否正在运行
  2. [root@tang ~]# systemctl status mysqld 
  3. ● mysqld.service - MySQL Server
  4.    Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
  5.    Active: active (running) since 日 2022-07-03 12:35:47 CST; 3min 21s ago
  6.      Docs: man:mysqld(8)
  7.            http://dev.mysql.com/doc/refman/en/using-systemd.html
  8.   Process: 971 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)
  9.  Main PID: 1414 (mysqld)
  10.    Status: "Server is operational"
  11.    CGroup: /system.slice/mysqld.service
  12.            └─1414 /usr/sbin/mysqld
  14. 7月 03 12:35:40 tang systemd[1]: Starting MySQL Server...
  15. 7月 03 12:35:47 tang systemd[1]: Started MySQL Server.
  17. #2. 停止MySQL服务
  18. [root@tang ~]# systemctl stop mysqld
  20. #3. 查看已经安装的MySQL包
  21. [root@tang ~]# rpm -qa | grep -i mysql 
  22. mysql-community-client-plugins-8.0.28-1.el7.x86_64
  23. mysql-community-icu-data-files-8.0.28-1.el7.x86_64
  24. mysql-community-common-8.0.28-1.el7.x86_64
  25. mysql-community-libs-8.0.28-1.el7.x86_64
  26. mysql-community-client-8.0.28-1.el7.x86_64
  27. mysql-community-server-8.0.28-1.el7.x86_64
  28. mysql-community-libs-compat-8.0.28-1.el7.x86_64
  30. #4. 卸载并删除MySQL组件服务，--nodeps强制删除
  31. [root@tang ~]# rpm -ev --nodeps mysql-community-client-plugins-8.0.28-1.el7.x86_64
  32. 软件包准备中...
  33. mysql-community-client-plugins-8.0.28-1.el7.x86_64
  34. [root@tang ~]# rpm -ev --nodeps mysql-community-icu-data-files-8.0.28-1.el7.x86_64
  35. 软件包准备中...
  36. mysql-community-icu-data-files-8.0.28-1.el7.x86_64
  37. [root@tang ~]# rpm -ev --nodeps mysql-community-common-8.0.28-1.el7.x86_64
  38. 软件包准备中...
  39. mysql-community-common-8.0.28-1.el7.x86_64
  40. [root@tang ~]# rpm -ev --nodeps mysql-community-libs-8.0.28-1.el7.x86_64
  41. 软件包准备中...
  42. mysql-community-libs-8.0.28-1.el7.x86_64
  43. [root@tang ~]# rpm -ev --nodeps mysql-community-client-8.0.28-1.el7.x86_64
  44. 软件包准备中...
  45. mysql-community-client-8.0.28-1.el7.x86_64
  46. [root@tang ~]# rpm -ev --nodeps mysql-community-server-8.0.28-1.el7.x86_64
  47. 软件包准备中...
  48. mysql-community-server-8.0.28-1.el7.x86_64
  49. 警告：/etc/my.cnf 已另存为 /etc/my.cnf.rpmsave
  50. [root@tang ~]# rpm -ev --nodeps mysql-community-libs-compat-8.0.28-1.el7.x86_64
  51. 软件包准备中...
  52. mysql-community-libs-compat-8.0.28-1.el7.x86_64
  53. [root@tang ~]# rm /etc/my.cnf.rpmsave
  55. #5. 删除MySQL的目录文件和库
  56. [root@tang ~]# find / -name mysql
  57. /etc/selinux/targeted/active/modules/100/mysql
  58. /etc/selinux/targeted/tmp/modules/100/mysql
  59. /var/lib/mysql
  60. /var/lib/mysql/mysql
  61. /opt/package/mysql
  63. [root@tang ~]# rm -rf /etc/selinux/targeted/active/modules/100/mysql
  64. [root@tang ~]# rm -rf /etc/selinux/targeted/tmp/modules/100/mysql
  65. [root@tang ~]# rm -rf /var/lib/mysql
  66. [root@tang ~]# rm -rf /var/lib/mysql/mysql
  67. [root@tang ~]# rm -rf /opt/package/mysql
  69. #6. 删除MySQL用户及组
  70. [root@tang ~]# id mysql
  71. uid=27(mysql) gid=27(mysql) 组=27(mysql)
  73. [root@tang ~]# id mysql
  74. uid=27(mysql) gid=27(mysql) 组=27(mysql)
  75. [root@tang ~]# userdel mysql
  76. [root@tang ~]# groupdel mysql
  77. groupdel：“mysql”组不存在
  78. [root@tang ~]# cat /etc/passwd |grep mysql #验证用户是否被删除
  79. [root@tang ~]# cat /etc/group |grep mysql #验证用户组是否被删除
  81. #7. 检查是否还有MySQL
  82. [root@tang ~]# rpm -qa|grep -i mysql
  83. 无结果，说明MySQL已经卸载干净