@Override
  public Stream<Pair<byte[], byte[]>> streamFromKey(
      final SegmentIdentifier segmentIdentifier, final byte[] startKey) {
    final RocksIterator rocksIterator = getDB().newIterator(safeColumnHandle(segmentIdentifier));
    rocksIterator.seek(startKey);
    return RocksDbIterator.create(rocksIterator).toStream();
  }
Safe method to map segment identifier to column handle.

@param segment segment identifier
@return column handle
plugins/rocksdb/src/main/java/org/hyperledger/besu/plugin/services/storage/rocksdb/segmented/RocksDBColumnarKeyValueStorage.java