[root@localhost ~]# rpm -ivh mysql-community-libs-8.0.18-1.el7.x86_64.rpm
warning: mysql-community-libs-8.0.18-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
error: Failed dependencies:
mariadb-libs is obsoleted by mysql-community-libs-8.0.18-1.el7.x86_64
解决办法：
[root@localhost ~]# yum remove mysql-libs
清除之前安装过的依赖包即可。