[fix](Nereids): TransposeSemiJoinAgg can't apply in Scalar Agg (apach…

…e#28434) Scalar Agg shouldn't be pushdown, it will cause wrong result
SWJTU-ZhangLei · Dec 15, 2023 · 0f93ee8 · 0f93ee8
1 parent 8986bb6
commit 0f93ee8
Show file tree

Hide file tree

Showing 2 changed files with 16 additions and 0 deletions.
diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/rewrite/TransposeSemiJoinAgg.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/rewrite/TransposeSemiJoinAgg.java
@@ -51,6 +51,10 @@ public Rule build() {
     public static boolean canTranspose(LogicalAggregate<? extends Plan> aggregate,
             LogicalJoin<? extends Plan, ? extends Plan> join) {
         Set<Slot> canPushDownSlots = PushDownFilterThroughAggregation.getCanPushDownSlots(aggregate);
+        // avoid push down scalar agg.
+        if (canPushDownSlots.isEmpty()) {
+            return false;
+        }
         Set<Slot> leftConditionSlot = join.getLeftConditionSlot();
         return canPushDownSlots.containsAll(leftConditionSlot);
     }

diff --git a/...e-core/src/test/java/org/apache/doris/nereids/rules/rewrite/TransposeSemiJoinAggTest.java b/...e-core/src/test/java/org/apache/doris/nereids/rules/rewrite/TransposeSemiJoinAggTest.java
@@ -18,6 +18,7 @@
 package org.apache.doris.nereids.rules.rewrite;
 
 import org.apache.doris.common.Pair;
+import org.apache.doris.nereids.trees.expressions.functions.agg.Sum;
 import org.apache.doris.nereids.trees.plans.JoinType;
 import org.apache.doris.nereids.trees.plans.logical.LogicalOlapScan;
 import org.apache.doris.nereids.trees.plans.logical.LogicalPlan;
@@ -49,4 +50,15 @@ void simple() {
                 );
     }
 
+    @Test
+    void rejectScalarAgg() {
+        LogicalPlan plan = new LogicalPlanBuilder(scan1)
+                .agg(ImmutableList.of(), ImmutableList.of((new Sum(scan1.getOutput().get(0))).alias("sum")))
+                .join(scan2, JoinType.LEFT_SEMI_JOIN, Pair.of(0, 0))
+                .build();
+        PlanChecker.from(MemoTestUtils.createConnectContext(), plan)
+                .applyTopDown(new TransposeSemiJoinAgg())
+                .matchesFromRoot(leftSemiLogicalJoin(logicalAggregate(), logicalOlapScan()));
+    }
+
 }