fix

Signed-off-by: before-Sunrise <[email protected]>
StarRocks · Feb 7, 2025 · eb2792e · eb2792e
1 parent 52691d3
commit eb2792e
Showing 1 changed file with 26 additions and 12 deletions.
diff --git a/fe/fe-core/src/main/java/com/starrocks/sql/optimizer/OutputPropertyDeriver.java b/fe/fe-core/src/main/java/com/starrocks/sql/optimizer/OutputPropertyDeriver.java
@@ -350,6 +350,7 @@ public PhysicalPropertySet visitPhysicalHashAggregate(PhysicalHashAggregateOpera
     public PhysicalPropertySet visitPhysicalRepeat(PhysicalRepeatOperator node, ExpressionContext context) {
         checkState(childrenOutputProperties.size() == 1);
         PhysicalPropertySet childPropertySet = childrenOutputProperties.get(0);
+        //
         List<ColumnRefOperator> subRefs = Lists.newArrayList(node.getRepeatColumnRef().get(0));
         node.getRepeatColumnRef().forEach(subRefs::retainAll);
         Set<ColumnRefOperator> allGroupingRefs = Sets.newHashSet();
@@ -358,19 +359,32 @@ public PhysicalPropertySet visitPhysicalRepeat(PhysicalRepeatOperator node, Expr
         subRefs.forEach(allGroupingRefs::remove);
 
         DistributionProperty childDistribution = childPropertySet.getDistributionProperty();
-        // update null distribution info to null relax for allGroupingRefs
-        if (!allGroupingRefs.isEmpty() && childDistribution.isShuffle()) {
-            HashDistributionSpec distributionSpec = (HashDistributionSpec) childDistribution.getSpec();
-            EquivalentDescriptor newEquivDesc = distributionSpec.getEquivDesc().copy();
-            newEquivDesc.clearNullStrictUnionFind();
-            HashDistributionSpec newDistributionSpec = distributionSpec.getNullRelaxSpec(newEquivDesc);
-            DistributionProperty newDistributionProperty = DistributionProperty.createProperty(
-                    newDistributionSpec,
-                    childPropertySet.getDistributionProperty().isCTERequired());
-            return new PhysicalPropertySet(newDistributionProperty, childPropertySet.getSortProperty(),
-                    childPropertySet.getCteProperty());
+        // only if the Intersection of RepeatColumnRef is the superset of the childrenOutputProperties
+        // we can use childrenOutputProperties as RepeatNode's output property
+        // such as RepeatColumnRef is (cola,colb),(cola), and childrenOutputProperties is hash(cola)
+        // since cola won't be inserted with null value, it's safe to use childrenOutputProperties
+        // if RepeatColumnRef is (cola,colb),(cola), and childrenOutputProperties is hash(cola,colb)
+        // since cola will be inserted with null value, it's unsafe to use hash(cola,colb)
+        DistributionProperty outputDistribution = EmptyDistributionProperty.INSTANCE;
+        if (childDistribution.isShuffle()) {
+            boolean canFollowChild = true;
+            HashDistributionSpec childDistributionSpec = (HashDistributionSpec) childDistribution.getSpec();
+            Set<Integer> commonRefs = subRefs.stream().map(ColumnRefOperator::getId).collect(Collectors.toSet());
+
+            for (DistributionCol col : childDistributionSpec.getHashDistributionDesc().getDistributionCols()) {
+                if (!commonRefs.contains(col.getColId())) {
+                    canFollowChild = false;
+                    break;
+                }
+            }
+
+            if (canFollowChild) {
+                outputDistribution = childDistribution;
+            }
         }
-        return childPropertySet;
+
+        return new PhysicalPropertySet(outputDistribution, childPropertySet.getSortProperty(),
+                childPropertySet.getCteProperty());
     }
 
     @Override