yum -y install mysql-community-server
Last metadata expiration check: 0:13:40 ago on Sun 26 Apr 2020 11:20:57 AM CST.
No match for argument: mysql-community-server
Error: Unable to find a match: mysql-community-server
解决：
先执行：yum module disable mysql
再执行：yum -y install mysql-community-server
配张图有理有据：