In Ruby on Rails, how do I create a table/model that has a field in it that references the same table? -

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i trying in rails 3. create table (syntax on code examples may not right, trying recreate memory):

create_table "persons", :force => true |t|     t.string "name"     t.integer "guest_of_id" end

and want guest_id reference row in persons table. each person guest of 1 person. in model set association:

class person < activerecord::base     belongs_to :guestof, :class => "person", :foreign_key => "guest_of_id" end

however, when try reference guestof field

a_person.guestof.name

i error 

undefined method 'eq' nil:nilclass

is possible in rails? doing wrong? missing has_many relationship? suspect google-fu failing me. possible solution have found http://railscasts.com/episodes/163-self-referential-association establishing many many relationship , think more complicated trying do.

thanks.

you should able do:

class person < activerecord::base     belongs_to :host, :class => "person", :foreign_key => "guest_of_id"     has_one :guest, :class => "person", :foreign_key => "guest_of_id" end

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