private void forwardLastBatch(VectorPTFOperator vecPTFOperator,
      BufferedVectorizedRowBatch lastBatch, Object[] partitionKey) throws HiveException {
    prepareBufferedBatchForForwarding(lastBatch, partitionKey);

    // Project with the output of our operator.
    overflowBatch.projectionSize = outputProjectionColumnMap.length;
    overflowBatch.projectedColumns = outputProjectionColumnMap;

    vecPTFOperator.forwardBatch(overflowBatch);
  }
Runs the evaluator on a specific range. The provided Ref<Object> is needed because some
evaluators (RANK, DENSE_RANK) are supposed to provide the result before handling the last batch
in a group (doLastBatchWork). For this purposes, a simple return value would not be sufficient.

@param evaluator
@param range
@param result
@throws HiveException
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/ptf/VectorPTFGroupBatches.java