Rake task to load production data (from Heroku) to the local dev database

load_db_from_heroku.rake

namespace :db do
  namespace :heroku do
    desc "capture DB Backup"
    task :capture_backup => :environment do
      if Rails.env == 'development'
        Bundler.with_clean_env do
          config = Rails.configuration.database_configuration[Rails.env]
          system "heroku pg:backups capture"
        end
      end
    end

    desc "Pull DB Backup"
    task :download_backup => :capture_backup do
      if Rails.env == 'development'
        Bundler.with_clean_env do
          config = Rails.configuration.database_configuration[Rails.env]
          system "curl -o latest.dump `heroku pg:backups public-url`"
        end
      end
    end

    desc "Load the PROD database from Heroku to the local dev database"
    task :load => :download_backup do
      if Rails.env == 'development'
        Bundler.with_clean_env do
          config = Rails.configuration.database_configuration[Rails.env]
          system <<-CMD
            pg_restore --verbose --clean --no-acl --no-owner -h localhost \
              -U #{config["username"]} -d #{config["database"]} latest.dump
            rm -rf latest.dump
          CMD
        end
      end
    end
  end
end

Updated for the new PGBackups (https://blog.heroku.com/archives/2015/3/11/pgbackups-levels-up)

In discussing this with a member of the Heroku Postgres staff, I have created a second version that uses pg:pull. The requirement there is that the target local database must not already exist. The workflow that I was trying to enable was pulling a prod copy for local dev, so there are a few additional steps around dropping and recreating some of the infrastructure.

I also learned that there are a lot of config settings that can effect how a queryplan executes, so benchmarking a query locally won't necessarily give the same plan as in prod.