Rails查询包含has_many并属于关联

Question

I have two model with following associations

class Application < ActiveRecord::Base
  belongs_to :registration
end

class Registration < ActiveRecord::Base
  has_many :applications, :dependent => :destroy
end

Now I am trying to do a query like this below

@applications = Application.includes(:registration).where("registration.stdniveau = ? AND uni_id = ? AND offer_sent = ? AND (offer_accepted =? OR offer_accepted =?)", 2, @uni.id, 1, nil, 1).references(:registration)

I also tried this

@applications = Application.includes(:registrations).where("registrations.stdniveau = ? AND uni_id = ? AND offer_sent = ? AND (offer_accepted =? OR offer_accepted =?)", 2, @uni.id, 1, nil, 1).references(:registrations)

But both query gives me unreadable error. I don't understand what am I missing here?

Answer 1

1) You should make your belongs_to singular: registration

2) If you want to make a conditional selection based on another table you need to join it.

3) So this should work:

Application.joins(:registration)
.where("registrations.stdniveau = ? AND uni_id = ? AND offer_sent = ? AND (offer_accepted =? OR offer_accepted =?)", 2, @uni.id, 1, nil, 1")