Rails - Apr 2006 - has_many :through

I have:

class Country < ActiveRecord::Base
  has_many :states
  has_many :cities, :through => :states
  has_many :places, :through => :cities
end


What is the query RoR is using when I type:

@places = @country.places

Is it only one query with joins?

-- 
Posted via http://www.ruby-forum.com/.

Wiktor  wrote:
> @places = @country.places
Replying to myself...

It doesn''t seem to work - cascading :through doesn''t work :(
Or am I doing something wrong?

-- 
Posted via http://www.ruby-forum.com/.

Well for a start I think you''ve misunderstood the usage of has_many
:through. The idea is that its a different way of writing
has_and_belongs_to_many. Your model should be:

class Country < ActiveRecord::Base
 has_many :states
end

class State < ActiveRecord::Base
 has_many :cities
end

class City < ActiveRecord::Base
 has_many :places
end

Hope this helps.
-Nathan
On 25/04/06, Wiktor <iktorn@gmail.com> wrote:
> Wiktor  wrote:
> > @places = @country.places
>
> Replying to myself...
>
> It doesn''t seem to work - cascading :through doesn''t work
:(
> Or am I doing something wrong?
>
> --
> Posted via http://www.ruby-forum.com/.
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