Question

hi I have two rails model

class Feedback < ActiveRecord::Base
  has_many :conversations, :dependent => :destroy

class Conversation < ActiveRecord::Base
  belongs_to :feedback, :touch => true

in the schema

create_table "conversations", :force => true do |t|
t.text     "content"
t.integer  "feedback_id"
t.datetime "created_at"
t.datetime "updated_at"
t.string   "author"
end

create_table "feedbacks", :force => true do |t|
t.datetime "created_at"
t.datetime "updated_at"
t.string   "status"
end

note that i have taken out columns and relationships from the models that do not matter for this question so please kindly don’t suggest I restructure the models differently

In my controller i have a method where I want to select feedbacks with status “unread” and whose last updated conversation’s author is “admin”

i know that the following selects feedbacks with status “unread”, but how do i expand on it to select those which meets my conversation author requirement?

@feedbacks = Feedback.where(:status => "unread")

---

I found this website (http://m.onkey.org/find-users-with-at-least-n-items) which seems to be doing something remotely similar in that it selects parent based on conditions related to child model, but still trying to figure out how to modify it for my case…

thanks much in advance!!!

Answer 1

It should work:

@feedbacks = Feedback.includes(:conversations).where("status = ? and conversations.author = ?", unread_state, admin_id).select{|a| a.conversations.last().author == admin}

Of course include your current values to the unread_status, admin and admin_id part.