1.下载mysql的linux安装包
2.将下载的二进制压缩包放到/usr/local/mysql目录下。（mysql需手动创建）
3.解压下载的zip包，
tar -xvf MySQL-5.6.38-1.el7.x86_64.rpm-bundle.tar
解压后有以下几个rpm包：
MySQL-client-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-devel-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-embedded-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-server-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-shared-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-shared-compat-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-test-advanced-5.6.38-1.el7.x86_64.rpm
3. 卸载MariaDB
查看当前安装的mariadb包：
[root@bogon 桌面]# rpm -qa | grep mariadb
将它们统统强制性卸载掉：
[root@bogon 桌面]# rpm -e --nodeps mariadb-libs-5.5.35-3.el7.x86_64
[root@bogon 桌面]# rpm -e --nodeps mariadb-5.5.35-3.el7.x86_64
[root@bogon 桌面]# rpm -e --nodeps mariadb-server-5.5.35-3.el7.x86_64
4.安装MySQL-client-advanced-5.6.38-1.el7.x86_64.rpm
安装perl后再次执行
5.安装 MySQL-devel-5.6.38-1.el7.x86_64.rpm
rpm -ivh MySQL-devel-5.6.38-1.el7.x86_64.rpm
6.安装MySQL-server-5.6.38-1.el7.x86_64.rpm
rpm -ivh MySQL-server-5.6.38-1.el7.x86_64.rpm
安装net-tools，再次安装
MySQL-client-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-devel-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-embedded-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-server-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-shared-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-shared-compat-advanced-5.6.38-1.el7.x86_64.rpm
MySQL-test-advanced-5.6.38-1.el7.x86_64.rpm
3. 卸载MariaDB
查看当前安装的mariadb包：
[root@bogon 桌面]# rpm -qa | grep mariadb
将它们统统强制性卸载掉：
[root@bogon 桌面]# rpm -e --nodeps mariadb-libs-5.5.35-3.el7.x86_64
[root@bogon 桌面]# rpm -e --nodeps mariadb-5.5.35-3.el7.x86_64
[root@bogon 桌面]# rpm -e --nodeps mariadb-server-5.5.35-3.el7.x86_64
4.安装MySQL-client-advanced-5.6.38-1.el7.x86_64.rpm
安装perl后再次执行
5.安装 MySQL-devel-5.6.38-1.el7.x86_64.rpm
rpm -ivh MySQL-devel-5.6.38-1.el7.x86_64.rpm
6.安装MySQL-server-5.6.38-1.el7.x86_64.rpm
rpm -ivh MySQL-server-5.6.38-1.el7.x86_64.rpm
安装net-tools，再次安装