Use postgresql in production environment

Author: tongkiat

Gemfile

@@ -46,3 +46,6 @@ group :development do
   gem 'spring'
 end
 
+group :production do
+  gem 'pg'
+end

Gemfile.lock

@@ -75,6 +75,7 @@ GEM
     multi_json (1.12.1)
     nokogiri (1.6.7.2)
       mini_portile2 (~> 2.0.0.rc2)
+    pg (0.18.4)
     rack (1.6.4)
     rack-test (0.6.3)
       rack (>= 1.0)
@@ -147,6 +148,7 @@ DEPENDENCIES
   coffee-rails (~> 4.1.0)
   jbuilder (~> 2.0)
   jquery-rails
+  pg
   rails (= 4.2.6)
   sass-rails (~> 5.0)
   sdoc (~> 0.4.0)