@Override
  protected QueryDataSource initQueryDataSource() {
    // Only a single file is involved here. Regardless of whether this file is sequence
    // or not, it is passed in as sequence file, which allows us to bypass some logic in
    // SeriesScanUtils that might fail.
    return new QueryDataSource(
        !seqFiles.isEmpty() ? seqFiles : unseqFiles, Collections.emptyList());
  }
Used for fixing files which contains internal unsorted data
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/compaction/execute/performer/impl/RepairUnsortedFileCompactionPerformer.java