I am new to linux and wants to understand the reason for using some commands. I am trying to install PostgreSQL on CentOs by following the instructions here.
First we do rpm -ivh pgdg-centos91-9.1-4.noarch.rpm
which installs the rpm package into the system. But why does it ask us to do yum install postgresql91-server
(which i assume installs postgresql) again if we have used rpm -ivh
to install the package?
Additionally, what is the reason for adding the lines exclude=postgresql*
into /etc/yum.repos.d/CentOS-Base.repo
under [base]
and [updates]
. Why is it that we exclude yum from accessing these packages, then use yum to install postgresql91-server
?