Ryan Williams.org

Getting Rails 3 to work with PostgreSQL 9.0 on Snow Leopard is pretty straight forward once you know what needs doing.

Installing PostgreSQL 9.0

I recommend using the 1 click installer of PostgreSQL available from EnterpriseDB. It makes installation very simple and will even let you automatically install addons such as PostGIS.

When that’s done you should have a PostgreSQL folder inside your Applications folder. Go ahead and launch pgAdmin from there and create a login role for your development database.

Installing the PostgreSQL Gem

You will need to install the pg gem to use PostgreSQL. So open up your Gemfile and add the line:

gem 'pg'

Unfortunately if you run bundle you will get an error when it tries to install “pg”. You will instead need to install it manually using the following command.

 sudo env ARCHFLAGS="-arch x86_64" \
  gem install pg -- \
  --with-pg-include=/Library/PostgreSQL/9.0/include/ \
  --with-pg-lib=/Library/PostgreSQL/9.0/lib/

Now run bundle to update your Gemfile.lock.

Once that’s all done you can edit your config/database.yml file and add the login role you setup previously.