static RecordIdentifier[] parseKeyIndex(Reader reader) {
    if (!reader.hasMetadataValue(OrcRecordUpdater.ACID_KEY_INDEX_NAME)) {
      return null;
    }

    ByteBuffer val =
        reader.getMetadataValue(OrcRecordUpdater.ACID_KEY_INDEX_NAME)
            .duplicate();
    return parseKeyIndex(val);
  }
make sure bucketProperty in the delete event is from the {@link row} rather than whatever
{@link this#bucket} is.  For bucketed tables, the 2 must agree on bucketId encoded in it
not for necessarily the whole value.  For unbucketed tables there is no relationship.
ql/src/java/org/apache/hadoop/hive/ql/io/orc/OrcRecordUpdater.java