centos7.9安装mysql8.0.28

curl -O https://cdn.mysql.com/archives/mysql-8.0/mysql-8.0.28-1.el7.x86_64.rpm-bundle.tar

tar -xvf mysql-8.0.28-1.el7.x86_64.rpm-bundle.tar
rpm -qa|grep mariadb
rpm -e --nodeps mariadb-libs
rpm -ivh mysql-community-common-8.0.28-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-plugins-8.0.28-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-8.0.28-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-8.0.28-1.el7.x86_64.rpm
rpm -ivh mysql-community-icu-data-files-8.0.28-1.el7.x86_64.rpm
yum install net-tools
yum install -y perl-Module-Install.noarch
rpm -ivh mysql-community-server-8.0.28-1.el7.x86_64.rpm


mysqld --initialize --console    #mysql初始化
chown -R mysql:mysql /var/lib/mysql/    #安装目录所有者权限修改一下
systemctl start mysqld        #启动mysql服务
cat /var/log/mysqld.log|grep localhost #这里是查看root临时密码
mysql -uroot -p    # 这里需要输入上面查到的临时密码
alter user 'root'@'localhost' identified by 'K123456a!';  #修改root密码为K123456a！

1.这里采用curl -O 的方法直接在服务器上下载到本地，不用xftp这种工具上传

2.rpm -qa|grep mariadb

这是检查服务器内是否有mariadb数据库，这个数据库与mysql有冲突，需要卸载，

rpm -e --nodeps mariadb-libs

忽视环境变量，直接卸载mariadb

3.后续的rpm是有顺序要求的，注意观察，不要选错了