Postgres packages to install on AWS Linux EC2 instance to access a Postgres RDS

Question

I have an RDS with PostGres as the database and an EC2 instance, Amazon Linux AMI. I will be installing a ruby on rails application on the EC2 instance. I see that one can use the following command on an ubuntu instance.

 sudo apt-get install postgres-client 

What would be the equivalent with a 'YUM' package manager on Amazon Linux AMI?

When I ran,

yum list postgresql*

I received the following list. Which of these packages are necessary on the EC2 instance?

postgresql95.x86_64 9.5.4-1.71.amzn1
postgresql95-contrib.x86_64 9.5.4-1.71.amzn1
postgresql95-devel.x86_64 9.5.4-1.71.amzn1
postgresql95-docs.x86_64 9.5.4-1.71.amzn1
postgresql95-libs.x86_64 9.5.4-1.71.amzn1
postgresql95-server.x86_64 9.5.4-1.71.amzn1
postgresql95-static.x86_64 9.5.4-1.71.amzn1
postgresql95-test.x86_64 9.5.4-1.71.amzn1

Thanks for the help!

Answer 1

Well the answer is that it depends on what some of your other libraries are going to use. However it's easier to tell you what's not needed. Since you already have postgresql installed on RDS what you don't need on the client machine (the one that's hosting your Ruby code) happen to be

postgresql95-server.x86_64 9.5.4-1.71.amzn1
postgresql95-test.x86_64 9.5.4-1.71.amzn1
postgresql95-contrib.x86_64 9.5.4-1.71.amzn1

anyway, there is absolutely no harm in installing additional packages. They will drink up only a tiny amount of extra space.