Linux（CentOS-8）安装MySQL8.0.11

CentOS安装MySQL8.0.11

总的思路就是：安装MySQL，编写配置文件，配置环境变量，成功开启服务，登陆并修改ROOT密码

开启远程访问的思路就是：授权用户所有IP都可以访问，系统的数据库端口放行

（安装步骤就不详细展开了，网上教程很多，步骤如下）

1. 下载解压mysql的压缩包,文件夹改名mysql

   tar -zxvf mysql-8.0.11-linux-glibc2.12-x86_64.tar.gz #解压安装包
   mv mysql-8.0.11-linux-glibc2.12-x86_64.tar.gz mysql #修改文件夹名称
   

2. 创建用户和用户组

   groupadd mysql #创建组
   useradd -g mysql mysql #创建用户
   

3. 创建data文件存放数据,并授权全部文件

   mkdir /mysql解压文件夹/data #创建data文件夹,用于存放数据库表
   chown -r -g mysql:mysql /mysql解压文件夹 #修改权限
   

4. 初始化数据库,并记录生成的随机密码

   bin/mysqld --initialize --user=mysql --basedir=/opt/mysql8.0 --datadir=/opt/mysql8.0/data #初始化MySQL,会生成默认密码,用于第一次登陆
   

5. 创建my.cnf配置文件文件配置MySQL

   因为mysql启动会自动寻找/etc/my.cnf配置文件,所以把配置文件放到/etc目录下,命名为my.cnf

   [mysqld]
   
   #Rove leading # and set to the amount of RAM for the most important data
   # cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
   # innodb_buffer_pool_size = 128M
   
   # Remove leading # to turn on a very important data integrity option: logging
   # changes to the binary log between backups.
   # log_bin
   
   # These are commonly set, remove the # and set as required.
   basedir = /opt/mysql
   datadir = /opt/mysql/data
   socket = /tmp/mysql.sock
   log-error = /opt/mysql/data/error.log
   pid-file = /opt/mysql/data/mysql.pid
   tmpdir = /tmp
   port = 3306
   #lower_case_table_names = 1
   # server_id = .....
   # socket = .....
   #lower_case_table_names = 1
   max_allowed_packet=32M
   default-authentication-plugin = mysql_native_password
   #lower_case_file_system = on
   #lower_case_table_names = 1
   log_bin_trust_function_creators = ON
   # Remove leading # to set options mainly useful for reporting servers.
   # The server defaults are faster for transactions and fast SELECTs.
   # Adjust sizes as needed, experiment to find the optimal values.
   # join_buffer_size = 128M
   # sort_buffer_size = 2M
   # read_rnd_buffer_size = 2M 
   
   sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
   

6. 设置开机自启动

   # cd /mysql解压目录/support-files/
   # cp mysql.server /etc/init.d/mysql
   # chmod +x /etc/init.d/mysql
   

7. 注册服务

   chkconfig --add mysql
   

8. etc/ld.so.conf要配置路径

   /mysql安装目录全路径/lib
   

9. 配置环境变量

   export PATH=$PATH:/mysql解压全路径/bin:/mysql解压全路径/lib
   

10. 启动MySQL,登陆，输入之前随机生成的密码

    service mysql start #启动mysql
    mysql -uroot -p #登陆
    
    然后输入之前初始化自动生成的密码登陆
    

11. 修改root密码

    alter user 'root'@'localhost' identified by '你的新的root账户密码';
    

开启MySQL远程访问

1. 修改root用户可访问的ip：host选项由loaclhost变更为%，意为允许所有ip登陆访问

   use mysql; #切换到mysql库
   update user set host ='%' where user='root'; #修改host为所有IP
   

2. 修改系统防火墙允许3306端口通过

3. MySQL8.0版本还需要修改密码的加密方式：

   先切换到mysql库

   use mysql
   

   一.修改加密方式

   ALTER USER'root'@'%' IDENTIFIED BY '你的密码' PASSWORD EXPIRE NEVER;
   

   二.修改密码

   ALTER USER'root'@'%' IDENTIFIED WITH mysql_native_password BY '你的密码';
   

   三.授权root用户可以远程访问

   GRANT ALL ON *.* TO 'root'@'%';
   

   四.刷新

   FLUSH PRIVILEGES;
   然后重启服务
   

4. 远程客户端打开sqlyog访问测试