Failed "bundle install" due to libpq-fe.h

I tried to run the command “bundle install” as follow and then I got

bundle install

Don’t run Bundler as root. Bundler can ask for sudo if it is needed, and
installing your bundle as root will break this application for all
users on this machine.
Fetching gem metadata from
Fetching additional metadata from
Resolving dependencies…
Using rake 10.0.4
Using i18n 0.6.4
Using multi_json 1.7.2
Using activesupport 3.2.8
Using builder 3.0.4
Using activemodel 3.2.8
Using erubis 2.7.0
Using journey 1.0.4
Using rack 1.4.5
Using rack-cache 1.2
Using rack-test 0.6.2
Using hike 1.2.1
Using tilt 1.3.6
Using sprockets 2.1.3
Using actionpack 3.2.8
Using mime-types 1.21
Using polyglot 0.3.3
Using treetop 1.4.12
Using mail 2.4.4
Using actionmailer 3.2.8
Using arel 3.0.2
Using tzinfo 0.3.37
Using activerecord 3.2.8
Using activeresource 3.2.8
Using bundler 1.6.2
Using coffee-script-source 1.6.2
Using execjs 1.4.0
Using coffee-script 2.2.0
Using rack-ssl 1.3.3
Using json 1.7.7
Using rdoc 3.12.2
Using thor 0.18.0
Using railties 3.2.8
Using coffee-rails 3.2.2
Using daemons 1.1.9
Using eventmachine 1.0.0
Using multi_xml 0.5.3
Using httparty 0.9.0
Using jquery-rails 2.2.1

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

/usr/local/rvm/rubies/ruby-2.1.1/bin/ruby extconf.rb

checking for pg_config… no
No pg_config… trying anyway. If building fails, please try again with
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.
need configuration options.

Provided configuration options:

extconf failed, exit code 1

Gem files will remain installed in
/usr/local/rvm/gems/ruby-2.1.1/gems/pg-0.14.1 for inspection.
Results logged to
An error occurred while installing pg (0.14.1), and Bundler cannot
Make sure that gem install pg -v '0.14.1' succeeds before bundling.

I have installed the “postgresql-devel” libraries

yum history info

Loaded plugins: fastestmirror, security
Transaction ID : 86
Begin time : Tue May 6 13:17:42 2014
Begin rpmdb : 813:9b44927673e9f4bb253ccef7cd2a9391187bab98
End time : 13:17:49 2014 (7 seconds)
End rpmdb : 815:f4686099b7e2b52a7c16eec9806299c2f0c74a18
User : root
Return-Code : Success
Command Line : install postgresql-devel
Transaction performed with:
Installed rpm-4.8.0-37.el6.i686 @base
Installed yum-3.2.29-43.el6.centos.noarch
Installed yum-plugin-fastestmirror-1.1.30-17.el6_5.noarch
Packages Altered:
Dep-Install postgresql92-9.2.8-1PGDG.rhel6.i686 @pgdg92
Install postgresql92-devel-9.2.8-1PGDG.rhel6.i686 @pgdg92

How I can fix this since I can’t start my application?