exclude ORDER BY clause when querying Relation#exists?

activerecord/lib/active_record/relation/finder_methods.rb

@@ -191,7 +191,7 @@ def exists?(id = false)
 
       join_dependency = construct_join_dependency_for_association_find
       relation = construct_relation_for_association_find(join_dependency)
-      relation = relation.except(:select).select("1").limit(1)
+      relation = relation.except(:select, :order).select("1").limit(1)
 
       case id
       when Array, Hash

activerecord/test/cases/finder_test.rb

@@ -57,6 +57,11 @@ def test_exists_with_nil_arg
     assert Topic.first.replies.exists?
   end
 
+  # ensures +exists?+ runs valid SQL by excluding order value
+  def test_exists_with_order
+    assert Topic.order(:id).uniq.exists?
+  end
+
   def test_does_not_exist_with_empty_table_and_no_args_given
     Topic.delete_all
     assert !Topic.exists?