fetchThingByField
  :: (PersistField typ, DBVal val)
  => EntityField val typ -> typ -> DB (Maybe (Entity val))
fetchThingByField field u =
  selectFirst [field ==. u] []
fetchThingByField
  :: (PersistField typ, DBVal val)
  => EntityField val typ -> typ -> DB (Maybe (Entity val))
fetchThingByField field u =
  selectFirst [field ==. u] []
fetchThingByField field u =
  selectFirst [field ==. u] []