gistfile1.txt

>> Pet.first(:name=>"Bo")
=> #<Pet id=1 name="Bo" kind="Portugese Water Dog">
>> toys = Toy.all
=> [#<Toy id=1 name="Chew Toy" price=nil>, #<Toy id=2 name="Squeaky Toy" price=nil>, #<Toy id=3 name="Bell Ball" price=nil>]
>> bo.toys = toys
=> [#<Toy id=1 name="Chew Toy" price=nil>, #<Toy id=2 name="Squeaky Toy" price=nil>, #<Toy id=3 name="Bell Ball" price=nil>]
>> bo.save
MysqlError: (mysql_errno=1062, sql_state=23000) Duplicate entry '1-1' for key 'PRIMARY'
Query: INSERT INTO `pets_toys` (`pet_id`, `toy_id`) VALUES (1, 1)
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/adapters/data_objects_adapter.rb:92:in `execute_non_query'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/adapters/data_objects_adapter.rb:92:in `execute'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/adapters/data_objects_adapter.rb:173:in `with_connection'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/adapters/data_objects_adapter.rb:90:in `execute'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/adapters/data_objects_adapter.rb:26:in `create'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/adapters/data_objects_adapter.rb:15:in `each'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/adapters/data_objects_adapter.rb:15:in `create'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/repository.rb:51:in `create'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/resource.rb:589:in `hookable__create_nan_before_advised'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:299:in `create'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:297:in `catch'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:297:in `create'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/resource.rb:295:in `hookable__save_nan_before_advised'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:299:in `save'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:297:in `catch'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:297:in `save'
... 6 levels...
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/support/kernel.rb:6:in `repository'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/associations/relationship.rb:172:in `with_repository'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/associations/one_to_many.rb:298:in `save_resource'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/associations/one_to_many.rb:210:in `save'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/lazy_array.rb:462:in `each'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/lazy_array.rb:462:in `each'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/associations/one_to_many.rb:309:in `send'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/associations/one_to_many.rb:309:in `method_missing'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/associations/one_to_many.rb:210:in `save'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/resource.rb:301:in `hookable__save_nan_before_advised'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/resource.rb:301:in `each'
	from /Library/Ruby/Gems/1.8/gems/dm-core-0.9.11/lib/dm-core/resource.rb:301:in `hookable__save_nan_before_advised'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:299:in `save'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:297:in `catch'
	from /Library/Ruby/Gems/1.8/gems/extlib-0.9.11/lib/extlib/hook.rb:297:in `save'
	from (irb):17>> 

gistfile2.rb

Extlib::Inflection.plural_word("human","humans")
class Human
  include DataMapper::Resource
  property :id, Serial
  property :first_name, String
  property :middle_name, String
  property :last_name, String
  
  has n, :ownerships, :child_key => [:human_id]
  has n, :pets, :through => :ownerships, :child_key => [:pet_id]
end

class Ownership
  include DataMapper::Resource
  property :human_id, Integer, :key => true
  property :pet_id,   Integer,   :key => true
  
  belongs_to :pet, :child_key => [:pet_id]
  belongs_to :human, :child_key => [:human_id]
end

class Pet
  include DataMapper::Resource
  property :id, Serial
  property :name, String
  property :kind, String
  
  has n, :ownerships, :child_key => [:pet_id]
  has n, :humans, :through  => :ownerships, :child_key => [:human_id]
  has n, :toys, :through => Resource
end

class Toy
  include DataMapper::Resource
  property :id, Serial
  property :name, String, :length => 255
  property :price, Integer

  has n, :pets, :through => Resource
end

gistfile3.rb

require 'rubygems'
require 'spec'
require 'dm-core'
require 'dm-aggregates'
require 'dm-types'
require 'many_through_models'

DataMapper.setup(:default, "mysql://localhost/dm_pets")
DataMapper.auto_migrate!

describe "behavior i expect out of an orm" do
  before(:all) do
    # Human.create( :first_name=>,:last_name=>)
    @barack   = Human.create( :first_name=>"Barack",  :last_name=>"Obama")
    @michelle = Human.create( :first_name=>"Michelle",:last_name=>"Obama")
    @malia    = Human.create( :first_name=>"Malia",:last_name=>"Obama")
    @sasha    = Human.create( :first_name=>"Sasha",:last_name=>"Obama")
    @bo       = Pet.create(   :name => "Bo", :kind=>"Portugese Water Dog")

    @gwb      = Human.create( :first_name=>"George", :middle_name=>"Walker",:last_name=>"Bush")
    @laura    = Human.create( :first_name=>"Laura",:last_name=>"Bush")
    @barney   = Pet.create(   :name => "Barney", :kind => "Scottish Terrier Dog")
    @beazly   = Pet.create(   :name => "Miss Beazley", :kind => "Scottish Terrier Dog")

    @bill     = Human.create( :first_name=>"Bill",:last_name=>"Clinton")
    @hillary  = Human.create( :first_name=>"Hillary",:last_name=>"Clinton")
    @chelsey  = Human.create( :first_name=>"Chelsey",:last_name=>"Clinton")
    @socks    = Pet.create(   :name => "Socks", :kind=> "American Shorthair Cat")
    @buddy    = Pet.create(   :name => "Buddy", :kind=> "Chocolate Labrador Retreiver Dog")
    @seamus   = Pet.create(   :name => "Seamus", :kind=> "Labrador Retreiver Dog")

    [@barack, @michelle, @malia, @sasha].each{ |p| Ownership.create(:human_id => p.id, :pet_id => @bo.id) }
    [@gwb, @laura].each{ |p| Ownership.create( :human_id => p.id, :pet_id => @barney.id) }
    [@bill,@hillary, @chelsey].each do |p| 
      Ownership.create( :human_id => p.id, :pet_id => @socks.id)
      Ownership.create( :human_id => p.id, :pet_id => @buddy.id)
      Ownership.create( :human_id => p.id, :pet_id => @seamus.id)
    end
  end

  it "should have an accessor for relationships" do
    @barack = Human.get(1)
    @barack.should respond_to(:ownerships)
    @barack.should respond_to(:pets)
  end
  
  it "should have at least one pet" do
    Human.all.pets.size.should > 1
  end
  
  it "should have finders which return on in property models" do
    Human.all(:last_name=>"Bush").size.should == 2
    Human.all(:middle_name.not => nil).should_not == []
  end
  
  it "should be able to find things by properties on immediate child models" do
    Human.all("ownerships.pet_id"=>Pet.first(:name=>"Bo").id).should == Human.all(:last_name => "Obama")
  end
  
  it "should be able to find things by properties on distant child models" do
    Human.all("ownerships.pet.name" => "Bo").should == Human.all(:last_name => "Obama")
    Human.all("ownerships.pet.name" => ["Socks","Buddy"]).should == Human.all(:last_name => "Clinton")
  end

=begin  
  it "should let you skip the near model (i.e. join table) when specifying a assocated model to query on" do
    Human.all("pets.name" => "Bo").should == Human.all(:last_name => "Obama")
    Human.all("pets.name" => ["Socks","Buddy"]).should == Human.all(:last_name => "Clinton")
  end
=end
end