Question

For some reason the view is blank even though there is data in the database.In the log shows sql statement selecting the tables but i dont really understand it,Can anybody help me ,what is going on here?Thanks in advance

controller

  @city = City.find(session[:city_id])
  @store_deals=StoreDeal.where("stores.city_id = ?", session[:city_id]).includes(:deal,  :store => [:city])

view

   <% @store_deals.each do |store_deal| %>
   <%= store_deal.deal.item_name %>
   <%= store_deal.store.store_name %>
   <%end%>

In the log

      SQL (0.3ms)  SELECT "store_deals"."id" AS t0_r0, "store_deals"."store_id" AS    t0_r1,    
     "store_deals"."deal_id" AS t0_r2, "store_deals"."created_at" AS t0_r3,   "store_deals". 
     "updated_at" AS t0_r4, "store_deals"."store_name" AS t0_r5, 
     "store_deals". "address" AS t0_r6, "deals"."id" AS t1_r0, "deals"."size" AS t1_r1,  "deals"."item_name" AS t1_r2, 
    "deals"."brand" AS t1_r3, "deals"."stars" AS t1_r4,  "deals"."created_at" AS t1_r5, "deals"."updated_at" AS t1_r6, "deals"."city_id" AS t1_r7, 
     "deals"."category_id" AS t1_r8, "deals"."price" AS t1_r9, "stores"."id" AS t2_r0, "stores"."store_name" AS t2_r1, "stores"."created_at" AS t2_r2, "stores".
     "updated_at" AS t2_r3, "stores"."address" AS t2_r4, "stores"."city_id" AS t2_r5, "cities"."id" AS t3_r0, "cities"."name" AS t3_r1, "cities".
    "created_at" AS t3_r2, "cities"."updated_at" AS t3_r3  FROM "store_deals" LEFT  OUTER JOIN "deals" ON "deals"."id" = "store_deals"."deal_id" LEFT 
     OUTER JOIN "stores" ON "stores"."id" = "store_deals"."store_id" LEFT OUTER JOIN  "cities" ON "cities"."id" = "stores"."city_id" WHERE (stores.city_id = 2)

Models

  class City < ActiveRecord::Base
  has_many :stores
  has_many :deals 
     end

    class Deal < ActiveRecord::Base
    belongs_to :city
    has_many :stores ,:through =>:store_deals
    has_many :store_deals
     end

  class StoreDeal < ActiveRecord::Base
  belongs_to :store
  belongs_to :deal
  end

Answer 1

That is the query that corresponds to your @store_deals = StoreDeal.where ... line. When you use includes Rails uses column aliases (e.g. AS t1_r5) to keep track of which columns in the results belong to which object when it creates objects from the results.

It’s likely your view is blank because @store_deals is empty, i.e. the query returned no rows. Have you tried inspecting it to see if it contains what you expect it to?