public static VectorHashKeyWrapperBatch compileKeyWrapperBatch(VectorExpression[] keyExpressions)
      throws HiveException
  {

    final int size = keyExpressions.length;
    TypeInfo[] typeInfos = new TypeInfo[size];
    for (int i = 0; i < size; i++) {
      typeInfos[i] = keyExpressions[i].getOutputTypeInfo();
    }
    return compileKeyWrapperBatch(keyExpressions, typeInfos);
  }
Helper method to assign values from a vector column into the key wrapper.
Optimized for IntervalDayTime type, no nulls, no repeat values, no selection vector.
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/wrapper/VectorHashKeyWrapperBatch.java