diff --git a/app/models/exchange.rb b/app/models/exchange.rb
index c85c2f9d8d..5566737a3f 100644
--- a/app/models/exchange.rb
+++ b/app/models/exchange.rb
@@ -38,7 +38,7 @@ class Exchange < ActiveRecord::Base
   }
   scope :with_any_variant, lambda { |variant_ids|
     joins(:exchange_variants).
-      where('exchange_variants.variant_id IN (?)', variant_ids).
+      where(exchange_variants: { variant_id: variant_ids }).
       select('DISTINCT exchanges.*')
   }
   scope :with_product, lambda { |product|
diff --git a/lib/open_food_network/products_cache.rb b/lib/open_food_network/products_cache.rb
index f099b43fba..089dc83030 100644
--- a/lib/open_food_network/products_cache.rb
+++ b/lib/open_food_network/products_cache.rb
@@ -165,13 +165,13 @@ module OpenFoodNetwork
     private_class_method :incoming_exchanges
 
     def self.outgoing_exchanges_affected_by(exchanges)
-      incoming_exchanges(exchanges).map do |incoming_exchange|
-        outgoing_exchanges_with_variants(
-          incoming_exchange.order_cycle,
-          incoming_exchange.variant_ids
-        )
-      end.flatten.uniq { |ex| [ex.receiver_id, ex.order_cycle_id]}
-      # Comparing only on these two ids is much faster.
+      incoming = incoming_exchanges(exchanges)
+      order_cycle_ids = incoming.select(:order_cycle_id)
+      variant_ids = ExchangeVariant.where(exchange_id: incoming).select(:variant_id)
+      Exchange.outgoing.
+        in_order_cycle(order_cycle_ids).
+        with_any_variant(variant_ids).
+        except(:select).select("DISTINCT receiver_id, order_cycle_id")
     end
     private_class_method :outgoing_exchanges_affected_by