@Override
    public TsFileResource getNextUnseqFileResource(boolean isDelete) {
      TsFileResource tsFileResource = dataSource.getUnseqResourceByIndex(curUnseqFileIndex);
      if (isDelete) {
        curUnseqFileIndex++;
      }
      return tsFileResource;
    }
Return true if taking first page reader from seq readers
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/source/SeriesScanUtil.java