private boolean judgeCanUseStatistics(
      final TAggregationType aggregationType, final TSDataType seriesType) {
    return !TSDataType.BLOB.equals(seriesType)
        || (!TAggregationType.LAST_VALUE.equals(aggregationType)
            && !TAggregationType.FIRST_VALUE.equals(aggregationType));
  }
This Visitor is responsible for transferring PlanNode Tree to Operator Tree.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/planner/OperatorTreeGenerator.java