ActiveRecord has_many associations

Given the models Country, State, City and Person as follows.

class Country < ActiveRecord::Base
has_many :states
end

class State < ActiveRecord::Base
belongs_to :country
has_many :cities
end

class City < ActiveRecord::Base
belongs_to :state
has_many :people
end

class Person < ActiveRecord::Base
belongs_to :city
end

Is there any way that doesn’t allow to delete a country if it has
states?
(will do the same for states and cities, cities and persons).
Didn’t saw nothing like that in the dependent option.

Thanks in advance.

Hi!

I’m new to Rails, but I’ll try to help.

Maybe you could use the before_destroy callback:

http://guides.rubyonrails.org/active_record_validations_callbacks.html#destroying-an-object

Best Regards,

Everaldo