https://dev.mysql.com/downloads/ 因为我是下载mysql5.7要在归档包里查找 选择对应的安装版本： 下载如下rpm包，下载地址：https://downloads.mysql.com/archives/community/mysql-community-common-5.7.20-1.el7.x86_64.rpmmysql-community-libs-5.7.20-1.el7.x86_64.