Github user geraldss commented on a diff in the pull request:
https://github.com/apache/phoenix/pull/308#discussion_r205296815
--- Diff:
phoenix-core/src/main/java/org/apache/phoenix/execute/ClientAggregatePlan.java
---
@@ -135,17 +142,25 @@ public ResultIterator iterator(ParallelScanGrouper
scanGrouper, Scan scan) throw
aggResultIterator = new
ClientUngroupedAggregatingResultIterator(LookAheadResultIterator.wrap(iterator),
serverAggregators);
aggResultIterator = new
UngroupedAggregatingResultIterator(LookAheadResultIterator.wrap(aggResultIterator),
clientAggregators);
} else {
- if (!groupBy.isOrderPreserving()) {
- int thresholdBytes =
context.getConnection().getQueryServices().getProps().getInt(
- QueryServices.SPOOL_THRESHOLD_BYTES_ATTRIB,
QueryServicesOptions.DEFAULT_SPOOL_THRESHOLD_BYTES);
- List<Expression> keyExpressions =
groupBy.getKeyExpressions();
+ List<Expression> keyExpressions = groupBy.getKeyExpressions();
+ if (groupBy.isOrderPreserving()) {
+ aggResultIterator = new
ClientGroupedAggregatingResultIterator(LookAheadResultIterator.wrap(iterator),
serverAggregators, keyExpressions);
+ } else {
+ int thresholdBytes =
context.getConnection().getQueryServices().getProps().getInt
+ (QueryServices.SPOOL_THRESHOLD_BYTES_ATTRIB,
QueryServicesOptions.DEFAULT_SPOOL_THRESHOLD_BYTES);
List<OrderByExpression> keyExpressionOrderBy =
Lists.newArrayListWithExpectedSize(keyExpressions.size());
for (Expression keyExpression : keyExpressions) {
keyExpressionOrderBy.add(new
OrderByExpression(keyExpression, false, true));
}
- iterator = new OrderedResultIterator(iterator,
keyExpressionOrderBy, thresholdBytes, null, null,
projector.getEstimatedRowByteSize());
+
+ if (useHashAgg) {
+ boolean sort = orderBy == OrderBy.FWD_ROW_KEY_ORDER_BY;
--- End diff --
The GROUP BY cannot cause REV_ROW_KEY_ORDER_BY, because the GROUP BY cannot
specific or produce descending keys. This is a pre-existing assumption + design
in SORT_MERGE_JOIN. The SORT_MERGE_JOIN creates its own forward sort, and its
Tracker reports a forward sort.
---
