run

# File activerecord/lib/active_record/associations/preloader/association.rb, line 15
        def run
          if !preload_scope || preload_scope.empty_scope?
            owners.each do |owner|
              associate_records_to_owner(owner, records_by_owner[owner] || [])
            end
          else
            # Custom preload scope is used and
            # the association can not be marked as loaded
            # Loading into a Hash instead
            records_by_owner
          end
          self
        end