收到ActiveRecord的關係，但需要對象

Question

我寫了下面的類：

class Occupation < ActiveRecord::Base 
    has_many :pref_labels 
    has_many :cv_occupations 
    has_many :cvs, :through => :cv_occupations 
    validates_uniqueness_of :uri 

    # This function will return the specified label for the given language. 
    def label(language = Language.find_or_create_by_code(:en)) 
    self.pref_labels.where("language_id = #{language.id}") 
    end 
end 

class PrefLabel < ActiveRecord::Base 
    belongs_to :language 
    belongs_to :concept 
    belongs_to :skill 
    belongs_to :occupation 
    validates_uniqueness_of :value, :scope => [:language_id, :value] 
    validates_uniqueness_of :language_id, :scope => [:language_id, :value] 
end 

在我看來，我把以下內容：％TD = occupation.label（@language） 但這種回報作爲錯誤：

undefined method `value' for #<ActiveRecord::Relation:0x80c8368> 

我怎樣才能得到真正的對象返回而不是關係？我知道這事做與延遲加載....

Answer 1

變化

self.pref_labels.where("language_id = #{language.id}") 

要

self.pref_labels.where("language_id = #{language.id}").all #or .first if you only one the first one