Multiple distinct aggregate functions that cannot be transformed into…

… multi_distinct will result in an error.

fe/fe-core/src/main/java/org/apache/doris/nereids/jobs/executor/Rewriter.java

@@ -40,6 +40,7 @@
 import org.apache.doris.nereids.rules.rewrite.CheckAndStandardizeWindowFunctionAndFrame;
 import org.apache.doris.nereids.rules.rewrite.CheckDataTypes;
 import org.apache.doris.nereids.rules.rewrite.CheckMatchExpression;
+import org.apache.doris.nereids.rules.rewrite.CheckMultiDistinct;
 import org.apache.doris.nereids.rules.rewrite.CollectFilterAboveConsumer;
 import org.apache.doris.nereids.rules.rewrite.CollectProjectAboveConsumer;
 import org.apache.doris.nereids.rules.rewrite.ColumnPruning;
@@ -292,6 +293,7 @@ public class Rewriter extends AbstractBatchJobExecutor {
                     custom(RuleType.ADJUST_NULLABLE, AdjustNullable::new),
                     bottomUp(
                             new ExpressionRewrite(CheckLegalityAfterRewrite.INSTANCE),
+                            new CheckMultiDistinct(),
                             new CheckAfterRewrite()
                     )),
             topic("MATERIALIZED CTE", topDown(

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

@@ -0,0 +1,68 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package org.apache.doris.nereids.rules.rewrite;
+
+import org.apache.doris.nereids.exceptions.AnalysisException;
+import org.apache.doris.nereids.rules.Rule;
+import org.apache.doris.nereids.rules.RuleType;
+import org.apache.doris.nereids.trees.expressions.functions.agg.AggregateFunction;
+import org.apache.doris.nereids.trees.expressions.functions.agg.Avg;
+import org.apache.doris.nereids.trees.expressions.functions.agg.Count;
+import org.apache.doris.nereids.trees.expressions.functions.agg.GroupConcat;
+import org.apache.doris.nereids.trees.expressions.functions.agg.Sum;
+import org.apache.doris.nereids.trees.plans.Plan;
+import org.apache.doris.nereids.trees.plans.logical.LogicalAggregate;
+
+import com.google.common.collect.ImmutableSet;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * If there are multiple distinct aggregate functions that cannot
+ * be transformed into multi_distinct, an error is reported.
+ * The following functions can be transformed into multi_distinct:
+ * - count -> MULTI_DISTINCT_COUNT
+ * - sum -> MULTI_DISTINCT_SUM
+ * - avg -> MULTI_DISTINCT_AVG
+ * - group_concat -> MULTI_DISTINCT_GROUP_CONCAT
+ */
+public class CheckMultiDistinct extends OneRewriteRuleFactory {
+    private final ImmutableSet<Class<? extends AggregateFunction>> supportedFunctions =
+            ImmutableSet.of(Count.class, Sum.class, Avg.class, GroupConcat.class);
+
+    @Override
+    public Rule build() {
+        return logicalAggregate().then(agg -> checkDistinct(agg)).toRule(RuleType.CHECK_ANALYSIS);
+    }
+
+    private LogicalAggregate checkDistinct(LogicalAggregate<? extends Plan> aggregate) {
+        List<AggregateFunction> distinctFuncs = aggregate.getAggregateFunctions().stream()
+                .filter(AggregateFunction::isDistinct)
+                .collect(Collectors.toList());
+        if (aggregate.getDistinctArguments().size() > 1) {
+            for (AggregateFunction aggfunc : distinctFuncs) {
+                if (!supportedFunctions.contains(aggfunc.getClass())) {
+                    throw new AnalysisException(aggfunc.toString() + " can't support multi distinct.");
+                }
+            }
+        }
+
+        return aggregate;
+    }
+}

regression-test/suites/nereids_syntax_p0/analyze_agg.groovy

@@ -68,4 +68,9 @@ suite("analyze_agg") {
                  tt2.d,
                  tt2.c;
     """
+
+    test {
+        sql "select count(distinct t2.id), max(distinct t2.c) from t2"
+        exception "max(DISTINCT c#2) can't support multi distinct."
+    }
 }