There are two hard things in computer science: naming things and cache invalidation :).rb

# artist.rb
class Artist < ActiveRecord::Base
  has_many :works
  has_many :compositions, :through => :works
end

# composition.rb
class Composition < ActiveRecord::Base  
  has_many :works
  has_many :artists, :through => :works
end

# work.rb
class Work < ActiveRecord::Base  
  set_table_name :artist_works    # We really want to reflect the association somehow in the database
  belongs_to :artist
  belongs_to :composition
end


# -- script/console
>> a = Artist.first
=> #<Artist id: 1, first_name: "Bedřich", middle_name: nil, last_name: "Smetana", description: "Hudební skladatel a dirigent.", text: "Bedřich Smetana (2. března 1824 Litomyšl – 12....", nationality: "Česká Republika", published: true, created_at: "2008-08-15 10:41:57", updated_at: "2008-08-15 10:41:57">
>> a.compositions.first
=> #<Composition id: 1, title_cs: "Má vlast", title_en: "My Country", title_de: "Mein Vaterland", created_at: "2008-08-15 10:41:57", updated_at: "2008-08-15 10:41:57">
>> c = Composition.first
=> #<Composition id: 1, title_cs: "Má vlast", title_en: "My Country", title_de: "Mein Vaterland", created_at: "2008-08-15 10:41:57", updated_at: "2008-08-15 10:41:57">
>> c.artists
=> [#<Artist id: 1, first_name: "Bedřich", middle_name: nil, last_name: "Smetana", description: "Hudební skladatel a dirigent.", text: "Bedřich Smetana (2. března 1824 Litomyšl – 12....", nationality: "Česká Republika", published: true, created_at: "2008-08-15 10:41:57", updated_at: "2008-08-15 10:41:57">]