离线断网环境下在centos7上安装postgresql12

//1. 在有网且安装了centos7的测试服务器上
yum install https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/pgdg-redhat-repo-latest.noarch.rpm
mkdir pg12_rpm_packs
//1.1 下载pg server/client，contrib和其依赖的其他包，暂不安装
yum install --downloadonly --downloaddir=./pg12_rpm_packs postgresql12-server postgresql12 postgresql12-contrib
tar -czvf pg12_rpm_packs.tar.gz pg12_rpm_packs
sz pg12_rpm_packs.tar.gz

//2. 在客户内网安装了centos7的服务器上
rz pg12_rpm_packs.tar.gz
tar -xzvf pg12_rpm_packs.tar.gz
cd pg12_rpm_packs
rpm -ivh ./*

//3. postgresql jdbc驱动的正确下载位置(提供jdk6/7/8版本)
https://jdbc.postgresql.org/download.html

参考：
https://www.postgresql.org/download/linux/redhat/