How (and whether) to populate rails application with initial data

Try a rake task. For example:

1. Create the file /lib/tasks/bootstrap.rake
2. In the file, add a task to create your default user:

    namespace :bootstrap do
      desc "Add the default user"
      task :default_user => :environment do
        User.create( :name => 'default', :password => 'password' )
      end

      desc "Create the default comment"
      task :default_comment => :environment do
        Comment.create( :title => 'Title', :body => 'First post!' )
      end

      desc "Run all bootstrapping tasks"
      task :all => [:default_user, :default_comment]
    end

3. Then, when you’re setting up your app for the first time, you can do rake db:migrate OR rake db:schema:load, and then do rake bootstrap:all.