unable to install pg gem

Question

I had this problem, this worked for me:

Install the postgresql-devel package, this will solve the issue of pg_config missing.

sudo apt-get install libpq-dev

Issue is gem dependency so before installing pg make sure you have installed "libpq-dev"

Ubuntu systems:

sudo apt-get install libpq-dev

RHEL systems:

yum install postgresql-devel

Mac:

brew install postgresql

gem install pg -- --with-pg-config=/usr/pgsql-9.1/bin/pg_config

@Winfield said it:

The pg gem requires the postgresql client libraries to bind against. This error usually means it can't find your Postgres libraries. Either you don't have them installed or you may need to pass the --with-pg-dir= to your gem install.

More than that, you only need --with-pg-config= to install it.

On a Mac

If, by any chance, you also installed postgres through the website bundle on mac, it will be on somewhere like /Applications/Postgres.app/Contents/Versions/9.3/bin.

So, either you pass it on the gem install:

gem install pg -- --with-pg-config=/Applications/Postgres.app/Contents/Versions/9.3/bin/pg_config

Or you set the PATH properly. Since that might be too much, to temporarily set the PATH:

export PATH=%PATH:/Applications/Postgres.app/Contents/Versions/9.3/bin/

I hadn't postgresql installed, so I just installed it using

sudo apt-get install postgresql postgresql-server-dev-9.1

on Ubuntu 12.04.

This solved it.

---

Update:

Use the latest version:

sudo apt-get install postgresql-9.3 postgresql-server-dev-9.3

This worked in my case:

sudo apt-get install libpq-dev

I used:

• Ubuntu 14.04.2 LTS
• Ruby 2.2.2
• Rails 4.2.1