ruby on rails - How to search for the fields of the parent model through child model in polymorphic association -

class book < activerecord::base   belongs_to :owner, polymorphic: true end  class user < active record::base   has_many :books, as: :owner end 

now book has 3 fields - name, owner_id , owner_type. need search name of user through books.

something ..

book.includes(:user).where("user_name ?","bla") 

can me this?

if this:

 book.includes(:owner) 

can not eagerly load polymorphic association

you error above.

you need define relationship between book , user

 class book < activerecord::base       belongs_to :owner, polymorphic: true       belongs_to :user, foreign_key: 'owner_id', conditions: "owner_type = 'user'"  end 

see here