Create migration with new setting

db/migrate/20200908094810_add_new_setting_to_namespace_setting.rb

+# frozen_string_literal: true
+
+class AddNewSettingToNamespaceSetting < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def up
+    with_lock_retries do
+      add_column :namespace_settings, :allow_mfa_for_subgroups, :boolean, default: true, null: false
+    end
+  end
+
+  def down
+    with_lock_retries do
+      remove_column :namespace_settings, :allow_mfa_for_subgroups, :boolean, default: true, null: false
+    end
+  end
+end

db/schema_migrations/20200908094810

+327cd19cd6c0f273aea61ffebf10046fb7229516bc4ed28f3c0290bb3ad04755
\ No newline at end of file

db/structure.sql

@@ -13445,7 +13445,8 @@ CREATE TABLE public.namespace_settings (
     created_at timestamp with time zone NOT NULL,
     updated_at timestamp with time zone NOT NULL,
     namespace_id integer NOT NULL,
-    prevent_forking_outside_group boolean DEFAULT false NOT NULL
+    prevent_forking_outside_group boolean DEFAULT false NOT NULL,
+    allow_mfa_for_subgroups boolean DEFAULT true NOT NULL
 );
 
 CREATE TABLE public.namespace_statistics (