discourse/db/migrate/20130906081326_rename_system_username.rb

class RenameSystemUsername < ActiveRecord::Migration[4.2]
  def up
    execute "update site_settings set name = 'site_contact_username' where name = 'system_username'"
  end

  def down
    execute "update site_settings set name = 'system_username' where name = 'site_contact_username'"
  end
end