private void mergeTimeValuePair(TimeValuePair from, TimeValuePair to) {
    if (!isAlign) {
      // ignore not aligned TimeValuePair with same timestamp
      return;
    }
    TsPrimitiveType[] fromVector = from.getValue().getVector();
    TsPrimitiveType[] toVector = to.getValue().getVector();
    for (int i = 0; i < toVector.length; i++) {
      if (toVector[i] == null && fromVector[i] != null) {
        toVector[i] = fromVector[i];
      }
    }
    to.getValue().setVector(toVector);
  }
Used for fixing files which contains internal unsorted data
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/compaction/execute/utils/writer/RepairUnsortedFileCompactionWriter.java