How to handle Ruby on Rails error: "Please install the postgresql adapter: `gem install activerecord-postgresql-adapter'"
The problem is not what anyone wrote.The problem is that the name of the postgresql database adapter is "postgresql", not "postgres", though the name of the GEM is "pg".
The definition in the database.yml file should include
adapter: postgresql
Here's the answer I got from Heroku and it worked for me (after trying different pg gems, adapters, and everything else on the 10 other posts about this)
1) add the line: gem 'pg' to your Gemfile.
2) Run the command bundle install to install the gem into your bundle.
3) Stage the Gemfile and Gemfile.lock changes: git add Gemfile Gemfile.lock
4) Commit the changes: git commit -m "Install the pg gem"
5) Redeploy to heroku: git push heroku master
This means you don’t have the new ‘pg’ postgresql library installed. This is easily fixed with a bit of:
sudo gem install pgI (Dov) found other solutions on the web which described setting GEM_HOME and adding ~/.gem/ruby/vers/bin to your PATH, but they didn't work. This solution above was provided byMark Mansour on his blog State of Flux at:http://stateofflux.com/2008/7/13/activerecord-postgresql-adapter-in-rails-2-1/