Uploading to Heroku DB rake:migrate problem

Question

having a problem with a heroku upload. Quite new to RoR so please excuse the beginners question.

I'm following the Ruby on Rails Tutorial (http://ruby.railstutorial.org), and after the scaffolding, I type heroku rake db:migrate and get the following error:

rake aborted! Please install the postgresql adapter: gem install activerecord-postgresql-adapter (pg is not part of the bundle. Add it to Gemfile.)

Tasks: TOP => db:migrate => db:load_config (See full trace by running task with --trace)

First time around, no problem, but this time I'm getting this error. Any ideas?

Sounds like you need to run the command gem install activerecord-postgresql-adapter. — Alex
@Alex I have indeed tried that, and that pulls up the error ERROR: Could not find a valid gem 'activerecord-postgresql-adapter' (>= 0) in any repository ERROR: Possible alternatives: activerecord-jdbcpostgresql-adapter, activerecord-postgis-adapter, activerecord-jdbcmssql-adapter, activerecord-jdbcmysql-adapter, activerecord-postgresql-cursors — David Archer
Have you added pg to your Gemfile and run bundle install? — sscirrus
@sscirrus yes, and Using pg (0.11.0) is in there while installing. — David Archer

Simone Carletti Simone Carletti · Accepted Answer · 2011-09-21T08:18:08

By default, a new Rails application is configured to use the SQLite3 database. Heroku doesn't support SQLite3, you must use PostgreSQL.

You have two alternatives:

Keep using SQLite3 in development and test, and switch to PostgreSQL in production.
Switch to PostgreSQL

Either ways, you need to add the pg gem to your Gemfile (assuming you are using Rails 3) and remove sqlite3.

# Gemfile
gem 'pg'

If you want to use Sqlite3 in development and test

# Gemfile
group :development, :test do
  gem 'sqlite3'
end

group :production do
  gem 'pg'
end

You might also need to change your database.yml configuration accordingly.

Uploading to Heroku DB rake:migrate problem

2 Answers