while_odometer_has_not_run_to_completion... {
  $id2++;
  (
    $data{$id}{$id2}{'key1'},
    $data{$id}{$id2}{'key2'},
    $data{$id}{$id2}{'key3'}, 
  )
    = 
  (
    $hash{$id}{'key1'}[ $odometer[0] ],
    $hash{$id}{'key2'}[ $odometer[1] ],
    $hash{$id}{'key3'}[ $odometer[2] ],
  );
  next_odometer( \@odometer );
}