Potential fix for one of the issues mentioned in #49

Reduces the number of SQL queries used on group_orders/index and
group_orders/archive, but adds extra  complexity to the code

app/models/order.rb

@@ -125,6 +125,20 @@ class Order < ApplicationRecord
     self
   end
 
+  # fetch current Order scope's records and map the current user's GroupOrders in (if any)
+  # (performance enhancement as opposed to fetching each GroupOrder separately from the view)
+  def self.ordergroup_group_orders_map(ordergroup)
+    orders = includes(:supplier)
+    group_orders = GroupOrder.where(ordergroup_id: ordergroup.id, order_id: orders.map(&:id))
+    group_orders_hash = Hash[group_orders.collect {|go| [go.order_id, go]}]
+    orders.map do |order|
+      {
+        order: order,
+        group_order: group_orders_hash[order.id]
+      }
+    end
+  end
+
   # search GroupOrder of given Ordergroup
   def group_order(ordergroup)
     group_orders.where(:ordergroup_id => ordergroup.id).first