Rails 5 - Joins null association without using join?

Question

What do I want

What I need to get all orders without acceptance for a given user, but I'm having issues with the first part only.

What do I have

Here are my models

class Order < ApplicationRecord
  has_one :acceptance
end

class Acceptance < ApplicationRecord
  belongs_to :order
end

What have I tried

I have already checked this answers

But they applied for a has_many - belongs to scenario (which is, presumably, why they fail). My scenario is simpler: has_one - belongs_to.

So far (after trying by myself, and reading other SO questions) the following have failed.

Order.includes(:acceptance).where(acceptance: { id: nil})
Order.left_outer_joins(:acceptance).where(acceptance: { id: nil })
Order.joins(:acceptance).merge(Acceptance.where(order_id: nil, id: nil))

Moreover, I can't do Order.joins(:acceptance) because that immediately fetches orders with an acceptance associated, I want the opposite of that.

Didn't seem that hard a priori, but it's giving a mild pain.

Peter Balaban · Accepted Answer · 2017-10-23T18:51:49.967

1

Order.includes(:acceptance).where(acceptances: { id: nil}) should work. You have missed s at the end. When you construct the query using where statement with nested hash parameters, first key is always table name

edited Oct 23 '17 at 18:51

answered Oct 23 '17 at 18:31

Peter Balaban

653
3
7

Nevermind about last comment, just read wrong. Is there a way to **not use** table names and keep everything between models? – Sebastialonso Oct 23 '17 at 18:34
No, I don't think so. If you do not want to use hard coded table name, then you can use `Acceptance.table_name` instead – Peter Balaban Oct 23 '17 at 18:39
Ok, will have to do. Thanks! – Sebastialonso Oct 23 '17 at 19:00

Rails 5 - Joins null association without using join?

What do I want

What do I have

What have I tried

1 Answers1