如何操作has_many上的数据：通过Ruby on Rails上的ActiveRecords上的关联？

Question

The documentation is a little poor in this aspect. If I have this tables

 Physicians Table
-----------
id integer
name string

Appointments table
----------------
id integer
physician_id integer
patient_id integer
appointment_date datetime

Patients table
---------------
id integer
name string 

and this models:

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

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

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

how do I do to insert an appointment on the database? It's not clear at all in the Rails webpage

Answer 1

This is a quite broad question actually. To insert a record in the database you can do one of three things.

1. Appointment.create(patient_id: 1, physician_id: 1, apt_date: DateTime.now)

2. If you have an instance of the Patient model lets call it patient and you want to assign in to physician with id=2 then

   patient.appointments.create(physician_id: 2, apt_date: DateTime.now)

3. If you have an instance of the Physician model called physician then

   physician.appointments.create(patient_id: 10, apt_date: DateTime.now)