has_many:通过NameError:未初始化的常量

时间:2013-01-15 22:08:58

标签: ruby-on-rails-3 console has-many-through

我只想制作一个小连接表,最终在该连接上存储额外的信息(这就是我不使用HABTM的原因)。从关联的rails文档中我创建了以下模型:

class Physician < ActiveRecord::Base
  has_many :appointments
  has_many :patients, :through => :appointments
end

class Patient < ActiveRecord::Base
  has_many :appointments
  has_many :physicians, :through => :appointments
end

class Appointment < ActiveRecord::Base
  belongs_to :physicians
  belongs_to :patients
end

我的架构如下所示:

ActiveRecord::Schema.define(:version => 20130115211859) do

  create_table "appointments", :force => true do |t|
    t.datetime "date"
    t.datetime "created_at",   :null => false
    t.datetime "updated_at",   :null => false
    t.integer  "patient_id"
    t.integer  "physician_id"
  end

  create_table "patients", :force => true do |t|
    t.string   "name"
    t.datetime "created_at", :null => false
    t.datetime "updated_at", :null => false
  end

  create_table "physicians", :force => true do |t|
    t.string   "name"
    t.datetime "created_at", :null => false
    t.datetime "updated_at", :null => false
  end

end

当我在控制台中时,我创建了一个医生和患者实例:

@patient = Patient.create!
@physician = Physician.create!

尝试将一个与另一个相关联

@physician.patients << @patient

我得到了

NameError: uninitialized constant Physician::Patients

以前曾询问过有关此示例的问题,但没有一个解决我的问题。有什么想法吗?

谢谢, 尼尔,铁路新手。

1 个答案:

答案 0 :(得分:17)

belongs_to模型中的Appointment来电应采用单数形式,而不是复数形式:

class Appointment < ActiveRecord::Base
  belongs_to :physician
  belongs_to :patient
end