Linux安装和卸载MySQL5.7详细教程

一、序

二、MySQL安装详细步骤

更新软件包

一、序

MySQL5.7是我们平时常用的Web数据库之一，Linux下安装和卸载可能会遇到不少坑，本文以Centos7下安装和卸载社区版MySQL5.7为例，详细记录了安装和卸载过程，方便大家参考，喜欢的可以点赞收藏，关注咱不迷路。

操作系统	MySQL
Centos7.9	MySQL5.7社区版

注意：确保以root用户身份登录系统安装

二、MySQL安装详细步骤

更新软件包

yum update -y

检查是否安装过MySQL

rpm -qa | grep -i mysql

如果发现已经安装过，可参考第四部分的MySQL卸载

下载Yum源配置文件

# noarch表示该软件包不依赖特定Linux发行版
wget https://dev.mysql.com/get/mysql57-community-release-el7-11.noarch.rpm

安装Yum源配置文件

执行安装命令

rpm -ivh mysql57-community-release-el7-11.noarch.rpm

缺省会在/etc/yum.repos.d目录下生成两个配置文件

安装MySQL服务器

yum -y install mysql-community-server

默认会安装以下5个rpm包

注意：此处可能安装失败，提示Public key for mysql-community-common-5.7.43-1.el7.x86_64.rpm is not installed异常信息：

问题原因：MySQL秘钥过期导致

解决方法：导入新的秘钥信息

rpm --import https://repo.mysql.com/RPM-GPG-KEY-mysql-2022

重新执行安装，出现如下信息表示安装成功

启动MySQL服务器

systemctl start mysqld

查看MySQL状态

systemctl status mysqld

active (running)表示已经启动成功正在运行

查看MySQL版本

mysql -V

执行结果

获取临时密码

grep "password" /var/log/mysqld.log

执行结果

设置root密码

首次登录可使用如下两种方式设置root密码：

运行安全脚本(生产环境推荐)

执行安全脚本，加固MySQL安全性，设置新的root密码

mysql_secure_installation

输入临时root密码

设置新的root密码，缺省安全策略是MEDIUM，要求至少包含8个字符，其中至少有一个大小写字母，一个特殊字符，一个数字，否则报 ... Failed! Error: Your password does not satisfy the current policy requirements异常。

输入要求的密码后可继续如下配置

Estimated strength of the password: 100 
Do you wish to continue with the password provided?(Press y|Y for Yes, any other key for No) : y
By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them. This is intended only for
testing, and to make the installation go a bit smoother.
You should remove them before moving into a production
environment.

# 移除匿名用户
Remove anonymous users? (Press y|Y for Yes, any other key for No) : y
Success.  


Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.

# 禁用远程root登录
Disallow root login remotely? (Press y|Y for Yes, any other key for No) : y
Success.

By default, MySQL comes with a database named 'test' that
anyone can access. This is also intended only for testing,
and should be removed before moving into a production
environment.

# 删除测试数据库及权限
Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y
 - Dropping test database...
Success.

 - Removing privileges on test database...
Success.

Reloading the privilege tables will ensure that all changes
made so far will take effect immediately.

# 重新加载授权表
Reload privilege tables now? (Press y|Y for Yes, any other key for No) : y
Success.

All done!

修改安全策略

执行登录

mysql -uroot -p

输入临时密码，进入MySQL

修改安全策略,使用简单密码登录

# 查看当前安全策略
show variables like 'validate_password%';
# 最低安全策略(0->LOW ,1->MEDIUM, 2->STRONG)
set global validate_password_policy=0; 
# 最小密码字符长度是4
set global validate_password_length=4; 
# 设置本机root密码
alter user 'root'@'localhost' identified by 'root';

设置成功后，输入quit命令使用修改后的密码重新登录，该方法只是临时生效重启MySQL后会失效，如果需要永久生效，需要修改/etc/my.conf重启MySQL服务。

设置开机启动

systemctl enable mysqld

停止MySQL服务器

systemctl stop mysqld

三、MySQL使用示例

远程访问

登录本机，针对root用户赋权和设置密码

# 授权，all表示所有ddl和dml操作权限，*.*表示针对所有数据库所有表，%表示本机和远程主机均能访问
grant all privileges on *.* to 'root'@'%' identified by '123456' with grant option;
# 刷新权限
flush privileges;

关闭本机防火墙

systemctl stop firewalld

通过远程主机执行，输入密码即可访问

mysql -h 192.168.5.11 -uroot -p

结果