morrySnow commented on code in PR #12274:
URL: https://github.com/apache/doris/pull/12274#discussion_r961842352
##########
fe/fe-core/src/main/java/org/apache/doris/nereids/rules/rewrite/logical/PruneAggChildColumns.java:
##########
@@ -54,15 +59,63 @@ public class PruneAggChildColumns extends
OneRewriteRuleFactory {
@Override
public Rule build() {
return
RuleType.COLUMN_PRUNE_AGGREGATION_CHILD.build(logicalAggregate().then(agg -> {
+ Slot slot = handleAggregateConstant(agg);
+ List<Slot> childOutput = agg.child().getOutput();
+ if (slot != null) {
+ if (childOutput.size() == 1 &&
childOutput.get(0).equals(slot)) {
+ return agg;
+ }
+ return agg.withChildren(ImmutableList.of(new
LogicalProject<>(ImmutableList.of(slot), agg.child())));
+ }
List<Expression> slots = Lists.newArrayList();
slots.addAll(agg.getExpressions());
Set<Slot> outputs = SlotExtractor.extractSlot(slots);
- List<NamedExpression> prunedOutputs =
agg.child().getOutput().stream().filter(outputs::contains)
+ List<NamedExpression> prunedOutputs =
childOutput.stream().filter(outputs::contains)
.collect(Collectors.toList());
if (prunedOutputs.size() == agg.child().getOutput().size()) {
return agg;
}
return agg.withChildren(ImmutableList.of(new
LogicalProject<>(prunedOutputs, agg.child())));
}));
}
+
+ /**
+ * For these aggregate function with constant param. Such as:
+ * count(*), count(1), sum(1)..etc.
+ */
+ private Slot handleAggregateConstant(LogicalAggregate<GroupPlan> agg) {
Review Comment:
add a @return comment to explain which situation this function will return
null.
BTW, for uniform code style, we'd better return Option<Slot> rather than
Slot with nullable
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org
For additional commands, e-mail: commits-h...@doris.apache.org
