hw3

day_2/tn_rails_concurrent/app/controllers/orders_controller.rb

@@ -1,6 +1,28 @@
+# frozen_string_literal: true
 class OrdersController < ApplicationController
   def top_products_report
-    top_products = Order.all
+    top_products = Order
+      .with(
+        daily_orders: Order
+          .select('product_id, DATE(created_at) AS order_date, SUM(quantity) AS total_quantity')
+          .group('product_id, DATE(created_at)'),
+      )
+      .from('daily_orders AS d')
+      .joins(<<~SQL.squish)
+        LEFT JOIN products AS p ON d.product_id = p.id
+          AND d.total_quantity = p.orders_count
+      SQL
+      .select('d.order_date, d.product_id, d.total_quantity')
+      .order(total_quantity: :desc )
+      .limit(10)
+      .map do |row|
+        {
+          date:           row.order_date,
+          product_id:     row.product_id,
+          total_quantity: row.total_quantity,
+        }
+      end
+
     render json: top_products
   end
 end

day_2/tn_rails_concurrent/app/models/order.rb

@@ -10,7 +10,7 @@
 #  updated_at     :datetime         not null
 #
 class Order < ApplicationRecord
-  belongs_to :product
+  belongs_to :product, counter_cache: true
 
   scope :pending, -> { where(current_status: :pending) }
   scope :processed, -> { where(current_status: :processed) }

day_2/tn_rails_concurrent/db/migrate/20241226023934_add_index_to_orders.rb

@@ -0,0 +1,6 @@
+class AddIndexToOrders < ActiveRecord::Migration[7.1]
+  disable_ddl_transaction!
+  def change
+    add_index :orders, :product_id, algorithm: :concurrently
+  end
+end

day_2/tn_rails_concurrent/db/migrate/20241226024546_add_orders_count_to_product.rb

@@ -0,0 +1,5 @@
+class AddOrdersCountToProduct < ActiveRecord::Migration[7.1]
+  def change
+    add_column :products, :orders_count, :integer, default: 0, null: false
+  end
+end

day_2/tn_rails_concurrent/db/migrate/20241227012439_add_fn_index_to_orders.rb

@@ -0,0 +1,6 @@
+class AddFnIndexToOrders < ActiveRecord::Migration[7.1]
+  disable_ddl_transaction!
+  def change
+    add_index :orders, 'DATE(created_at)', name: 'index_orders_on_created_at_date', algorithm: :concurrently
+  end
+end

day_2/tn_rails_concurrent/db/structure.sql

@@ -9,6 +9,13 @@ SET xmloption = content;
 SET client_min_messages = warning;
 SET row_security = off;
 
+--
+-- Name: public; Type: SCHEMA; Schema: -; Owner: -
+--
+
+-- *not* creating schema, since initdb creates it
+
+
 --
 -- Name: order_status; Type: TYPE; Schema: public; Owner: -
 --
@@ -79,7 +86,8 @@ CREATE TABLE public.products (
     stock integer,
     price numeric,
     created_at timestamp(6) without time zone NOT NULL,
-    updated_at timestamp(6) without time zone NOT NULL
+    updated_at timestamp(6) without time zone NOT NULL,
+    orders_count integer DEFAULT 0 NOT NULL
 );
 
 
@@ -157,13 +165,30 @@ ALTER TABLE ONLY public.schema_migrations
     ADD CONSTRAINT schema_migrations_pkey PRIMARY KEY (version);
 
 
+--
+-- Name: index_orders_on_created_at_date; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_orders_on_created_at_date ON public.orders USING btree (date(created_at));
+
+
+--
+-- Name: index_orders_on_product_id; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_orders_on_product_id ON public.orders USING btree (product_id);
+
+
 --
 -- PostgreSQL database dump complete
 --
 
 SET search_path TO "$user", public;
 
 INSERT INTO "schema_migrations" (version) VALUES
+('20241227012439'),
+('20241226024546'),
+('20241226023934'),
 ('20241216120643'),
 ('20241216120641');