@Override
  public Set<byte[]> getAllKeysThat(
      final SegmentIdentifier segment, final Predicate<byte[]> returnCondition) {
    return streamKeys(segment).filter(returnCondition).collect(toUnmodifiableSet());
  }
Instantiates a new RocksDb columnar key value snapshot.

@param db the db
@param metrics the metrics
plugins/rocksdb/src/main/java/org/hyperledger/besu/plugin/services/storage/rocksdb/segmented/RocksDBColumnarKeyValueSnapshot.java