code: function getLastItem(payload) {
      const builtQuery = buildQuery(payload);
      const newPayload = {
        ...builtQuery,
        pageSize: null,
        queryParams: (builtQuery.queryParams || []).concat("limitToLast=1")
      };
      const { dbref, orderBy, key } = refBuilder(newPayload);
      dbref
        .once("child_added")
        .then(snap => dispatch(actions.setLastItem({ snap, name: key, orderBy })))
        .catch(console.error);
    }
docs: function removeListener (ref) { var dbref = db.ref(ref) dbref.off('value') }