private boolean containsAvgStddevVarCall(List<AggregateCall> aggCallList) {
    for (AggregateCall call : aggCallList) {
      if (isReducible(call.getAggregation().getKind())) {
        return true;
      }
    }
    return false;
  }
Returns whether any of the aggregates are calls to AVG, STDDEV_*, VAR_*.

@param aggCallList List of aggregate calls
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveAggregateReduceFunctionsRule.java