unable to install pg gem

Question

I tried using gem install pg but it doesn't seem to work.

gem install pg gives this error

Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing pg:
        ERROR: Failed to build gem native extension.

C:/Ruby/bin/ruby.exe extconf.rb
checking for pg_config... no
No pg_config... trying anyway. If building fails, please try again with
 --with-pg-config=/path/to/pg_config
checking for libpq-fe.h... no
Can't find the 'libpq-fe.h header
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=C:/Ruby/bin/ruby
        --with-pg
        --without-pg
        --with-pg-dir
        --without-pg-dir
        --with-pg-include
        --without-pg-include=${pg-dir}/include
        --with-pg-lib
        --without-pg-lib=${pg-dir}/lib
        --with-pg-config
        --without-pg-config
        --with-pg_config
        --without-pg_config


Gem files will remain installed in C:/Ruby/lib/ruby/gems/1.8/gems/pg-0.10.1 for
inspection.
Results logged to C:/Ruby/lib/ruby/gems/1.8/gems/pg-0.10.1/ext/gem_make.out

Solution 1

Answered here: Can't install pg gem on Windows

There is no Windows native version of latest release of pg (0.10.0) released yesterday, but if you install 0.9.0 it should install binaries without issues.

Solution 2

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

Solution 3

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

Solution 4

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

Solution 5

@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/

View more solutions

Comments

[Noah W. Smith]

If you're on a mac, follow this tutorial: matthew.mceachen.us/blog/…

[0112]

@NatchiQ broken link?

[Raj]

in my case the error log said libpq was not found, so i installed sudo apt install postgresql postgresql-contrib libpq-dev pgadmin3 -y

[Jared Menard]

Try opening a new terminal tab and trying again. That worked for me. I had just installed psql, and the window I was trying to install the gem in didn't have psql in its path.

[Ryanmt]

Worked for me by apt-get install libpq-dev. Thanks for the hint.

[mraaroncruz]

and for me installing postgresql-server-dev-8.4 on ubuntu LTS 10

[Mark Berry]

Confirmation, from the pg gem Wiki homepage: "On Ubuntu, /usr/bin/pg_config is provided by the libpq-dev package."

[dfrankow]

postgresql-devel doesn't exist for debian squeeze. We used postgresql-server-dev-8.4 and that worked.

[Steve]

This helped me on a mac, anyone know what the default path is and how to change it?

[TuK]

This helped me (on Centos 6.2)

[Hiasinho]

Worked for me in openSUSE zypper in postgresql-devel. Fixed both the config & the libpq.

[Iain]

Had the same issue on Fedora 17 this answer solved it (I used yum install postgres-devel).

[Pedro]

Worked for me on OS X, but with path to /Applications/Postgres.app/Contents/MacOS/bin/pg_config (I have a standalone Postgres.app)

[Marek Kirejczyk]

Works on OS X Maveric

[gMale]

Fixed the problem for me but on a mac (with homebrew) I had to run this command: brew install postgresql

[Alex LaFroscia]

@Fivell Late to the game with the answer here, but if you have Homebrew installed, brew install postgresql will get you the packages you need.

[skilleo]

gem install pg -- --with-pg-config=/Applications/Postgres.app/Contents/Version‌​s/9.4/bin/pg_config on yosemite with Postgres App

[Dan Sandland]

for specific version: gem install pg -v '0.17.1' -- --with-pg-config=/Applications/Postgres.app/Contents/Version‌​s/9.3/bin/pg_config

[Hoang Le]

The answer for Mac is true. It's just because we haven't installed PostgreSQL on the machine.

[Mahattam]

@Fivell try brew install postgresql on mac

[Benoit]

Thanks, it also works using brew installed postgreSQL # PostgreSQL bin path export PATH=$PATH:/usr/local/Cellar/postgresql/9.5.0/bin/

[Janusz Lenar]

Worked. But on Mac, preceding with env ARCHFLAGS="-arch x86_64" was a game changer for me.

[HarlemSquirrel]

Worked for me on OS X 10.11 with psql app 9.6 and gem version 0.18.4 gem install pg -v '0.18.4' -- --with-pg-config=/Applications/Postgres.app/Contents/Version‌​s/9.6/bin/pg_config

[Lane Rettig]

Yes! This was all I needed! Install on clean OS X, no Postgres.app

[Arthur]

On Centos 7 yum install postgresql-devel solved my error related to pg_config for installing the 'pg' .gem. By the way I opted to use the just released PostgreSQL 10

[Tim Krins]

I used gem install pg -- --with-pg-config=/Applications/Postgres.app/Contents/Version‌​s/latest/bin/pg_conf‌​ig for OSX 10.12

[Stephen Silber]

There is a symlink folder called latest inside of the Postgres.app contents folder that is useful in case 9.3 is no longer shipped. gem install pg -- --with-pg-config=/Applications/Postgres.app/Contents/Version‌​s/latest/bin/pg_conf‌​ig

[racar]

This help me on OS X with no brew support (using postgres installer)

[luigi7up]

Thanks! I switched from brew installed postgres to Postgress.app and had this problem

[Greg]

macOS Monterey M1. Added to .zshrc export PATH=$PATH:/Applications/Postgres.app/Contents/Versions/14/b‌​in/ and gem install pg worked and could then `bundle install in Rails