gistfile1.rb

namespace :db do
  
  desc "Perform automigration"
  task :automigrate => :environment do
    ::DataMapper::AutoMigrator.auto_migrate
  end
  
  desc "Perform non destructive automigration"
  task :autoupgrade => :environment do
    ::DataMapper::AutoMigrator.auto_upgrade
  end
 
  namespace :migrate do
    task :load => :environment do
      gem 'dm-migrations'
      FileList["db/migrations/*.rb"].each do |migration|
        load migration
      end
    end
 
    desc "Migrate up using migrations"
    task :up, :version, :needs => :load do |t, args|
      version = args[:version]
      migrate_up!(version)
    end
    
    desc "Migrate down using migrations"
    task :down, :version, :needs => :load do |t, args|
      version = args[:version]
      migrate_down!(version)
    end
  end
 
  desc "Migrate the database to the latest version"
  task :migrate => 'db:migrate:up'
end