"postgresql gem is not loaded" error deploying a Ruby on Rails application on Heroku

Question

I am trying to use postgresql with Ruby on Rails on Heroku but got an error

Specified 'postgresql' for database adapter, but the gem is not loaded. Add `gem 'pg'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord). (Gem::LoadError)

Please help me to solve this issue.

Answer 1

This worked for me

gem 'pg', '~> 0.20'

Thanks to Piers C

Got this answer from

Heroku and Rails: Gem Load Error with Postgres, however it is Specified in GEMFILE