branch-2.1: [fix](nereids) fix merge_percentile_to_array when has same agg function #44783

fe/fe-core/src/main/java/org/apache/doris/nereids/rules/rewrite/MergePercentileToArray.java

@@ -152,10 +152,10 @@ private Plan doMerge(LogicalAggregate<Plan> aggregate) {
                 (List<Expression>) (List) newPercentileArrays);
         ImmutableList.Builder<NamedExpression> newProjectOutputExpressions = ImmutableList.builder();
         newProjectOutputExpressions.addAll((List<NamedExpression>) (List) notChangeForProject);
-        Map<Expression, Alias> existsAliasMap = Maps.newHashMap();
+        Map<Expression, List<Alias>> existsAliasMap = Maps.newHashMap();
         // existsAliasMap is used to keep upper plan refer the same expr
         for (Alias alias : existsAliases) {
-            existsAliasMap.put(alias.child(), alias);
+            existsAliasMap.computeIfAbsent(alias.child(), k -> new ArrayList<>()).add(alias);
         }
         Map<DistinctAndExpr, Slot> slotMap = Maps.newHashMap();
         // slotMap is used to find the correspondence
@@ -169,20 +169,22 @@ private Plan doMerge(LogicalAggregate<Plan> aggregate) {
         for (Map.Entry<DistinctAndExpr, List<AggregateFunction>> entry : funcMap.entrySet()) {
             for (int i = 0; i < entry.getValue().size(); i++) {
                 AggregateFunction aggFunc = entry.getValue().get(i);
-                Alias originAlias = existsAliasMap.get(aggFunc);
-                DistinctAndExpr distinctAndExpr = new DistinctAndExpr(aggFunc.child(0), aggFunc.isDistinct());
-                Alias newAlias = new Alias(originAlias.getExprId(), new ElementAt(slotMap.get(distinctAndExpr),
-                        new IntegerLiteral(i + 1)), originAlias.getName());
-                newProjectOutputExpressions.add(newAlias);
+                List<Alias> originAliases = existsAliasMap.get(aggFunc);
+                for (Alias originAlias : originAliases) {
+                    DistinctAndExpr distinctAndExpr = new DistinctAndExpr(aggFunc.child(0), aggFunc.isDistinct());
+                    Alias newAlias = new Alias(originAlias.getExprId(), new ElementAt(slotMap.get(distinctAndExpr),
+                            new IntegerLiteral(i + 1)), originAlias.getName());
+                    newProjectOutputExpressions.add(newAlias);
+                }
             }
         }
         newProjectOutputExpressions.addAll(groupBySlots);
-        return new LogicalProject(newProjectOutputExpressions.build(), newAggregate);
+        return new LogicalProject<>(newProjectOutputExpressions.build(), newAggregate);
     }
 
     private static class DistinctAndExpr {
-        private Expression expression;
-        private boolean isDistinct;
+        private final Expression expression;
+        private final boolean isDistinct;
 
         public DistinctAndExpr(Expression expression, boolean isDistinct) {
             this.expression = expression;
@@ -193,10 +195,6 @@ public Expression getExpression() {
             return expression;
         }
 
-        public boolean isDistinct() {
-            return isDistinct;
-        }
-
         @Override
         public boolean equals(Object o) {
             if (this == o) {

regression-test/data/nereids_rules_p0/merge_percentile_to_array/merge_percentile_to_array.out

@@ -41,3 +41,15 @@
 7.0	\N	\N
 7.0	7.0	7
 
+-- !same_percentile --
+52	1.0	1.0	2.0
+
+-- !same_percentile_group_by --
+\N	6.0	6.0	6.0
+2	3.0	3.0	3.0
+25	3.0	3.0	3.0
+4	2.0	2.0	2.0
+5	1.0	1.0	1.6
+7	6.0	6.0	6.0
+9	1.2	1.2	1.8
+

regression-test/suites/nereids_rules_p0/merge_percentile_to_array/merge_percentile_to_array.groovy

@@ -57,4 +57,8 @@ suite("merge_percentile_to_array") {
             percentile(abs(a), 0.55) as c2 from test_merge_percentile group by a) t;      
     """
 
+    order_qt_same_percentile """select sum(a),percentile(pk, 0.1) as c1 , percentile(pk, 0.1) as c2 ,
+            percentile(pk, 0.4) as c2 from test_merge_percentile;"""
+    order_qt_same_percentile_group_by """select sum(a),percentile(pk, 0.1) as c1 , percentile(pk, 0.1) as c2 ,
+            percentile(pk, 0.4) as c2 from test_merge_percentile group by a;"""
 }