I'm tried to deploy a new version of my app to heroku. The deployment fails because heroku says, that the gem pg is not in my GEMFILE ... I have this postgres gem in my GEMFILE. I also looked for some answers, but no one worked ... As anyone an idea?

I use Ruby 2.0.0p247, Rails 3.2.14 refinery-cms 2.1.0

Here is my Gemfile:

```
source 'https://rubygems.org'
ruby '2.0.0'

gem 'rails'
gem 'newrelic_rpm'

group :production do
  gem 'pg'
  gem 'fog'
end

# Gems used only for assets and not required
# in production environments by default.
group :assets do
  gem 'sass-rails'
  gem 'coffee-rails'

  # See https://github.com/sstephenson/execjs#readme for more supported runtimes
  # gem 'therubyracer', :platforms => :ruby

  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails'

# To use ActiveModel has_secure_password
# gem 'bcrypt-ruby'

# To use Jbuilder templates for JSON
 gem 'jbuilder'

# Use unicorn as the app server
 gem 'unicorn'

# Deploy with Capistrano
 gem 'capistrano'

# To use debugger
 gem 'debugger'

# The Heroku gem allows you to interface with Heroku's API
gem 'heroku'

# Fog allows you to use S3 assets (added for Heroku)
gem 'fog'

# Postgres support (added for Heroku)
#gem 'pg'

#Connecting to Amazon S3
gem 'aws-s3'
#gem 'taps'

# Refinery CMS
#gem 'refinerycms', '~> 2.0.0', :git => 'git://github.com/refinery/refinerycms.git', :branch => '2-0-stable'
gem 'refinerycms'

# Specify additional Refinery CMS Extensions here (all optional):
gem 'refinerycms-i18n'
#  gem 'refinerycms-blog', '~> 2.0.0'
#  gem 'refinerycms-inquiries', '~> 2.0.0'
#  gem 'refinerycms-search', '~> 2.0.0'
gem 'refinerycms-page-images'

gem 'refinerycms-announcements', :path => 'vendor/extensions'
gem 'refinerycms-publications', :path => 'vendor/extensions'
gem 'refinerycms-workers', :path => 'vendor/extensions'

```

And here the error message:

```
-----> Writing config/database.yml to read from DATABASE_URL
-----> Preparing app for Rails asset pipeline
       Running: rake assets:precompile
       rake aborted!
       Please install the postgresql adapter: `gem install activerecord-postgresql-adapter` (pg is not part of the bundle. Add it to Gemfile.)
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/bundler-1.3.2/lib/bundler/rubygems_integration.rb:214:in `block in replace_gem'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activerecord-3.2.14/lib/active_record/connection_adapters/postgresql_adapter.rb:7:in `<top (required)>'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:251:in `require'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:251:in `block in require'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:236:in `load_dependency'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:251:in `require'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activerecord-3.2.14/lib/active_record/connection_adapters/abstract/connection_specification.rb:50:in `resolve_hash_connection'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activerecord-3.2.14/lib/active_record/connection_adapters/abstract/connection_specification.rb:41:in `resolve_string_connection'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activerecord-3.2.14/lib/active_record/connection_adapters/abstract/connection_specification.rb:27:in `spec'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activerecord-3.2.14/lib/active_record/connection_adapters/abstract/connection_specification.rb:130:in `establish_connection'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activerecord-3.2.14/lib/active_record/railtie.rb:88:in `block (2 levels) in <class:Railtie>'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/lazy_load_hooks.rb:36:in `instance_eval'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/lazy_load_hooks.rb:26:in `block in on_load'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/lazy_load_hooks.rb:25:in `each'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/lazy_load_hooks.rb:25:in `on_load'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activerecord-3.2.14/lib/active_record/railtie.rb:80:in `block in <class:Railtie>'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/initializable.rb:30:in `instance_exec'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/initializable.rb:30:in `run'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/initializable.rb:55:in `block in run_initializers'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/initializable.rb:54:in `each'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/initializable.rb:54:in `run_initializers'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/application.rb:136:in `initialize!'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/railtie/configurable.rb:30:in `method_missing'
       /tmp/build_37zyls4tcoz59/config/environment.rb:5:in `<top (required)>'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:251:in `require'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:251:in `block in require'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:236:in `load_dependency'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/activesupport-3.2.14/lib/active_support/dependencies.rb:251:in `require'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/application.rb:103:in `require_environment!'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/railties-3.2.14/lib/rails/application.rb:305:in `block (2 levels) in initialize_tasks'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/actionpack-3.2.14/lib/sprockets/assets.rake:93:in `block (2 levels) in <top (required)>'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/actionpack-3.2.14/lib/sprockets/assets.rake:60:in `block (3 levels) in <top (required)>'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/actionpack-3.2.14/lib/sprockets/assets.rake:23:in `invoke_or_reboot_rake_task'
       /tmp/build_37zyls4tcoz59/vendor/bundle/ruby/2.0.0/gems/actionpack-3.2.14/lib/sprockets/assets.rake:29:in `block (2 levels) in <top (required)>'
       Tasks: TOP => environment
       (See full trace by running task with --trace)
       Precompiling assets failed, enabling runtime asset compilation
       Injecting rails31_enable_runtime_asset_compilation
       Please see this article for troubleshooting help:
       http://devcenter.heroku.com/articles/rails31_heroku_cedar#troubleshooting

```
['https://Stackoverflow.com/questions/18274428', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/1458773/']
according to the gemfile:

```
# Postgres support (added for Heroku)
#gem 'pg'

```

pg is commented-out. uncomment it to install it 

```
gem 'pg'

```

In my gemfile for instance, I work in windows, and heroku doesn't. So I have

```
gem "pg", '~> 0.15.1', :group => :production
group :development, :test do
    gem 'pg', "~> 0.15.1", :platform => [:mswin, :mingw]

```

since you must have some db installed, preferbly pg since it is heroku

also, as Gavin in the comments said - make sure you are in production, since it seems that heroku doesn't think o..
The problem is that you have the pg gem in the production group. Therefore when assets are precompiled on Heroku (which uses the global group + assets group) then the PG gem cannot indeed be found because it's in the production group.

I would suggest having the pg gem in the global group and available to allow asset groups.