if ($schemaVersion <= 60) {
    print STDERR <<QUOTE;
WARNING: Schema version 62 and 63 make nullable jobset_id fields on
         Builds and Jobs non-nullable. On big Hydra servers, this
         migration will take many hours. Because of that, the
         migration is not automatic, and must be performed manually.
         To backfill these IDs, run: hydra-fill-ids
QUOTE
}