官网下载yum源
centos6.X
rpm -Uvh https://repo.mysql.com//mysql80-community-release-el6-3.noarch.rpm
[root@localhost ~]# yum repolist all | grep mysql
mysql-cluster-7.5-community MySQL Cluster 7.5 Community 禁用
mysql-cluster-7.5-community-source MySQL Cluster 7.5 Community - Sou 禁用
mysql-cluster-7.6-community MySQL Cluster 7.6 Community 禁用
mysql-cluster-7.6-community-source MySQL Cluster 7.6 Community - Sou 禁用
mysql-cluster-8.0-community MySQL Cluster 8.0 Community 禁用
mysql-cluster-8.0-community-source MySQL Cluster 8.0 Community - Sou 禁用
mysql-connectors-community MySQL Connectors Community 启用: 102
mysql-connectors-community-source MySQL Connectors Community - Sour 禁用
mysql-tools-community MySQL Tools Community 启用: 81
mysql-tools-community-source MySQL Tools Community - Source 禁用
mysql-tools-preview MySQL Tools Preview 禁用
mysql-tools-preview-source MySQL Tools Preview - Source 禁用
mysql55-community MySQL 5.5 Community Server 禁用
mysql55-community-source MySQL 5.5 Community Server - Sour 禁用
mysql56-community MySQL 5.6 Community Server 禁用
mysql56-community-source MySQL 5.6 Community Server - Sour 禁用
mysql57-community MySQL 5.7 Community Server 禁用
mysql57-community-source MySQL 5.7 Community Server - Sour 禁用
mysql80-community MySQL 8.0 Community Server 启用: 113
mysql80-community-source MySQL 8.0 Community Server - Sour 禁用
安装5.7
修改/etc/yum.repos.d/mysql-community.repo 把修改成 enabled=1
[mysql57-community]
name=MySQL 5.7 Community Server
baseurl=http://repo.mysql.com/yum/mysql-5.7-community/el/6/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql
想要装哪个版本就可以把哪个改成1，其他都改成0
yum install mysql-community-server
service mysqld start
来源：https://blog.csdn.net/weixin_45452611/article/details/98874122