CentOS 7.8 安装 MySQL 5.7 教程

系统版本

命令：cat /etc/centos-release
输入：CentOS Linux release 7.8.2003 (Core)

安装方式

1. yum 安装
2. 编译安装(以后有时间介绍，不同的系统不同的版本，编译安装会有各种不同的问题)

yum 安装方式介绍

CentOS 7 默认安装了mariadb数据库，但是我们要使用MySQL

• 进入本机的源文件目录
  • cd /usr/local/src/
• 下载MySQL 5.7的repo源
  • wget http://repo.mysql.com/mysql57-community-release-el7-8.noarch.rpm
• 安装MySQL源
  • rpm -ivh mysql57-community-release-el7-8.noarch.rpm
• 使用yum安装mysql-server(这个过程可能要30分钟左右)
  • yum -y install mysql-server
• 安装完成
• 说明：如果是MySQL 8.0版本的安装源是：wget https://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm
• 参考：https://dev.mysql.com/downloads/repo/yum/

总下载量：208 M
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
(1/7): libaio-0.3.109-13.el7.x86_64.rpm                      |  24 kB  00:00:00
(2/7): mysql-community-common-5.7.29-1.el7.x86_64.rpm        | 311 kB  00:00:04
(3/7): mysql-community-libs-5.7.29-1.el7.x86_64.rpm          | 2.5 MB  00:01:39     
(4/7): mysql-community-libs-compat-5.7.29-1.el7.x86_64.rpm   | 1.3 MB  00:00:44     
(5/7): postfix-2.10.1-7.el7.x86_64.rpm                       | 2.4 MB  00:00:00     
(6/7): mysql-community-client-5.7.29-1.el7.x86_64.rpm        |  26 MB  00:09:19     
(7/7): mysql-community-server-5.7.29-1.el7.x86_64.rpm        | 175 MB  00:28:37

已安装:
  mysql-community-libs.x86_64 0:5.7.29-1.el7
  mysql-community-libs-compat.x86_64 0:5.7.29-1.el7
  mysql-community-server.x86_64 0:5.7.29-1.el7
  
作为依赖被安装:
  libaio.x86_64 0:0.3.109-13.el7
  mysql-community-client.x86_64 0:5.7.29-1.el7
  mysql-community-common.x86_64 0:5.7.29-1.el7
  
作为依赖被升级:
  postfix.x86_64 2:2.10.1-7.el7
  
替代:
  mariadb-libs.x86_64 1:5.5.56-2.el7
  
完毕！

数据库配置

• 启动MySQL：systemctl start mysqld.service
• 查看MySQL状态：systemctl status mysqld.service

● mysqld.service - MySQL Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
Active: active (running) since 五 2020-07-17 11:06:22 CST; 14s ago
Docs: man:mysqld(8)
http://dev.mysql.com/doc/refman/en/using-systemd.html
Process: 10007 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS (code=exited, status=0/SUCCESS)
Process: 9957 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)
Main PID: 10010 (mysqld)
CGroup: /system.slice/mysqld.service
└─10010 /usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysql...

7月 17 11:06:19 flyone systemd[1]: Starting MySQL Server...
7月 17 11:06:22 flyone systemd[1]: Started MySQL Server.

• 查找数据库root用户的 临时密码：grep "password" /var/log/mysqld.log

2020-07-17T03:06:20.464191Z 1 [Note] A temporary password is generated for root@localhost: Q8ry3siVj/ue

• 使用临时密码进入数据库：mysql -uroot -p
• 如果不修改密码，会有如下报错

mysql> show databases;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.

• 修改密码，如果密码太简单，会有如下报错

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123';
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

• 调整密码后：

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'Fly@123456';
Query OK, 0 rows affected (0.00 sec)

• 配置访问权限

mysql> update mysql.user set host='%' where host='localhost';
Query OK, 3 rows affected (0.00 sec)
Rows matched: 3  Changed: 3  Warnings: 0

• 或者

mysql> grant all on *.* to root@'%';       
Query OK, 0 rows affected (0.00 sec)

• 刷新权限(重要 ！！！)

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

• Done ！！！