diff --git a/app/controllers/announcements_controller.rb b/app/controllers/announcements_controller.rb
index e429be1..7e390db 100644
--- a/app/controllers/announcements_controller.rb
+++ b/app/controllers/announcements_controller.rb
@@ -129,7 +129,7 @@ class AnnouncementsController < ApplicationController
         if anns_cache.count > 1
           anns_cache.destroy
         end
-        AnnsCache.create(parent_id: subpart.id,locale: I18n.locale.to_s,filter_result: sorted_anns.map{|v| v.id})
+        AnnsCache.create(parent_id: subpart.id,locale: I18n.locale.to_s,filter_result: sorted_anns.pluck(:id))
       else
         sorted_anns = sorted_anns.sample(widget_data_count)
       end