private void iterateNoNullsRepeatingWithAggregationSelection(
    VectorAggregationBufferRow[] aggregationBufferSets,
    int aggregateIndex,
    long value,
    int batchSize) {

    for (int i=0; i < batchSize; ++i) {
      Aggregation myagg = getCurrentAggregationBuffer(
        aggregationBufferSets,
        aggregateIndex,
        i);
      myagg.sumValue(value);
    }
  }
Value is explicitly (re)initialized in reset()
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/aggregates/VectorUDAFSumDecimal64ToDecimal.java