gistfile1.rb

#!/usr/bin/env ruby -Ku
# encoding: utf-8
 
require 'rubygems'
require 'dm-core'
require 'dm-types'
 
DataMapper::Logger.new($stdout, :debug)
DataMapper.setup(:default, "sqlite3:///#{Dir.pwd}/examine.db") 


class Seating
  include DataMapper::Resource
  property :serial, Serial
  property :days, Flag[:monday, :tuesday, :wednesday, :thursday, :friday, :saturday, :sunday]              
end

DataMapper.auto_migrate!  

Seating.create(:days => [:monday, :tuesday]) # A
Seating.create(:days => [:tuesday]) # B
Seating.create(:days => [:monday, :tuesday, :wednesday, :thursday, :friday]) # C

p Seating.all(:days => [:tuesday]) # Returns only B
p Seating.all(:days => [:monday, :tuesday]) # Returns only B

# Sad emoticon :'(