[HIVE-12826] Vectorization: fix VectorUDAF* suspect isNull checks

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.3.0, 2.0.0, 2.1.0
• Fix Version/s: 2.0.0
• Component/s: Vectorization

Release Note

commit 36e855084da833915dfe6c34f74e19352b64fde9

    Vectorization: fix VectorUDAF* suspect isNull checks (Gopal V, reviewed by Matt McCline)
    
    Signed-off-by: Gopal V <[e-mail]>

• Assignee: Gopal Vijayaraghavan
• Reporter: Gopal Vijayaraghavan
• Created: 09/Jan/16 13:29
• Updated: 29/Jul/16 22:11
• Resolved: 18/Jan/16 23:37

Description

for isRepeating=true, checking isNull[selected[i]] might return incorrect results (without a heavy array fill of isNull).

VectorUDAFSum/Min/Max/Avg and SumDecimal impls need to be reviewed for this pattern.

    private void iterateHasNullsRepeatingSelectionWithAggregationSelection(
      VectorAggregationBufferRow[] aggregationBufferSets,
      int aggregateIndex,
      <ValueType> value,
      int batchSize,
      int[] selection,
      boolean[] isNull) {
      
      for (int i=0; i < batchSize; ++i) {
        if (!isNull[selection[i]]) {
          Aggregation myagg = getCurrentAggregationBuffer(
            aggregationBufferSets, 
            aggregateIndex,
            i);
          myagg.sumValue(value);
        }
      }
    }

Issue Links

• is required by: HIVE-12750 Vectorization logic not maintaining noNulls flag and isNull array properly causing wrong query results
• relates to: HIVE-11704 Create errata.txt file