docs: public static long getUniqueIdForFragment(PlanFragment frag) {
          long retval = 0;
          CatalogType parent = frag.getParent();
          retval = ((long) parent.getParent().getRelativeIndex()) << 32;
          retval += ((long) parent.getRelativeIndex()) << 16;
          retval += frag.getRelativeIndex();
  
          return retval;
      }