1 files changed, 14 insertions, 2 deletions
diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index 85343040db..1985b38f8a 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Associations
     class Preloader
@@ -103,7 +105,7 @@ module ActiveRecord
           end
 
           def records_for(ids, &block)
-            scope.where(association_key_name => ids).load(&block)
+            scope.where(association_key_name => ids.size == 1 ? ids.first : ids).load(&block)
           end
 
           def scope
@@ -114,8 +116,18 @@ module ActiveRecord
             @reflection_scope ||= reflection.scope_for(klass)
           end
 
+          def klass_scope
+            current_scope = klass.current_scope
+
+            if current_scope && current_scope.empty_scope?
+              klass.unscoped
+            else
+              klass.default_scoped
+            end
+          end
+
           def build_scope
-            scope = klass.default_scoped
+            scope = klass_scope
 
             if reflection.type
               scope.where!(reflection.type => model.base_class.sti_name)