Ruby Relationships without the database

ballroom.rb

class Ballroom

  # returns an array of all the ballroom titles
  def self.all_titles
    tables.collect { |x| x[0] }
  end

  # returns an array of table ids.
  def self.get(table)
    tables[table]
  end

  private

  # this is a listing of all the ballrooms by name. This is quite manual but since this data never changes, we're okay
  def self.districts
    #works like this:
    # "ballroom title" => [table1.id, table2.id ... tablen.id]
    {
      "The Grand Room" =>  (1..20).map,
      "Crystal Ballroom" => [21, 22],
      "Emerald Ballroom" => [23, 24, 25]
    }
  end
end

chairs.rb

class Chairs << ActiveRecord::Base     
    named_scope :chairs_in_ballroom, lambda { |table_ids|           
        { :conditions => ["table_id IN (?)", table_ids] }
     }
end