卸载mariadb 

解决安装mysql与mariadb冲突问题（卸载干净mariadb）_何妨徐行的博客-CSDN博客

安装rpm包前可能需要的命令：

yum install openssl-devel用于管理rpm包的工具

yum install lrzsz -y 文件传输缺乏rz  

下载安装包

去mysql官网 把rpm包不管是wget 还是手动上传都行给整到liunx服务器上

创建目录,并解压

mkdir mysql
​
tar -xvf mysql-8.0.26-1.el7.x86_64.rpm-bundle.tar -C mysql

安装mysql的安装包

cd mysql
​
rpm -ivh mysql-community-common-8.0.26-1.el7.x86_64.rpm 
​
rpm -ivh mysql-community-client-plugins-8.0.26-1.el7.x86_64.rpm 
​
rpm -ivh mysql-community-libs-8.0.26-1.el7.x86_64.rpm 
​
rpm -ivh mysql-community-libs-compat-8.0.26-1.el7.x86_64.rpm
​
yum install openssl-devel
​
rpm -ivh  mysql-community-devel-8.0.26-1.el7.x86_64.rpm
​
rpm -ivh mysql-community-client-8.0.26-1.el7.x86_64.rpm
​
rpm -ivh  mysql-community-server-8.0.26-1.el7.x86_64.rpm
​

如果报错

[root@iZ2zefj8x9bih185ymxnj7Z mysql]# rpm -ivh  mysql-community-server-8.0.26-1.el7.x86_64.rpm
warning: mysql-community-server-8.0.26-1.el7.x86_64.rpm: Header V3 DSA/SHA256 Signature, key ID 5072e1f5: NOKEY
error: Failed dependencies:
    libaio.so.1()(64bit) is needed by mysql-community-server-8.0.26-1.el7.x86_64
    libaio.so.1(LIBAIO_0.1)(64bit) is needed by mysql-community-server-8.0.26-1.el7.x86_64
    libaio.so.1(LIBAIO_0.4)(64bit) is needed by mysql-community-server-8.0.26-1.el7.x86_64
 

补上

yum install libaio

运行以下命令，启动并设置开机自启动MySQL服务。

sudo systemctl start mysqld

sudo systemctl enable mysqld

其他

systemctl start mysqld

systemctl restart mysqld

systemctl stop mysqld

查询自动生成的root用户密码

grep 'temporary password' /var/log/mysqld.log

命令行执行指令 :

mysql -u root -p

然后输入上述查询到的自动生成的密码, 完成登录 .

 修改root用户密码

登录到MySQL之后，需要将自动生成的不便记忆的密码修改了，修改成自己熟悉的便于记忆的密码。

ALTER  USER  'root'@'localhost'  IDENTIFIED BY '1234';

执行上述的SQL会报错，原因是因为设置的密码太简单，密码复杂度不够。我们可以设置密码的复杂度为简单类型，密码长度为4。

set global validate_password.policy = 0;
set global validate_password.length = 4;

降低密码的校验规则之后，再次执行上述修改密码的指令。

创建用户

默认的root用户只能当前节点localhost访问，是无法远程访问的，我们还需要创建一个账户，用户远程访问

create user 'dk'@'%' IDENTIFIED WITH mysql_native_password BY '1234';

并给root用户分配权限

grant all privileges on *.* to 'dk';

刷新权限

flush privileges; 
 

 重新连接MySQL