diff --git a/app/models/user_second_factor.rb b/app/models/user_second_factor.rb
index fcf17e14dce..dc7f1695c87 100644
--- a/app/models/user_second_factor.rb
+++ b/app/models/user_second_factor.rb
@@ -31,3 +31,7 @@ end
 #  created_at :datetime         not null
 #  updated_at :datetime         not null
 #
+# Indexes
+#
+#  index_user_second_factors_on_user_id  (user_id)
+#
diff --git a/db/migrate/20180716062012_add_index_user_id_on_user_second_factors.rb b/db/migrate/20180716062012_add_index_user_id_on_user_second_factors.rb
new file mode 100644
index 00000000000..86185644904
--- /dev/null
+++ b/db/migrate/20180716062012_add_index_user_id_on_user_second_factors.rb
@@ -0,0 +1,5 @@
+class AddIndexUserIdOnUserSecondFactors < ActiveRecord::Migration[5.2]
+  def change
+    add_index :user_second_factors, :user_id
+  end
+end