[fix](nereids) to_date should return type datev2 for datetimev2 (#21375)

To_date function in nereids return type should be DATEV2 if the arg type is DATETIMEV2.
Before the return type was DATE which would cause BE get wrong query result.

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/executable/DateTimeExtractAndTransform.java

@@ -522,9 +522,9 @@ public class DateTimeExtractAndTransform {
         return new DateLiteral(date.getYear(), date.getMonth(), date.getDay());
     }
 
-    @ExecFunction(name = "to_date", argTypes = {"DATETIMEV2"}, returnType = "DATE")
+    @ExecFunction(name = "to_date", argTypes = {"DATETIMEV2"}, returnType = "DATEV2")
     public static Expression toDate(DateTimeV2Literal date) {
-        return new DateLiteral(date.getYear(), date.getMonth(), date.getDay());
+        return new DateV2Literal(date.getYear(), date.getMonth(), date.getDay());
     }
 
     /**

regression-test/data/external_table_emr_p2/hive/test_hive_to_date.out

@@ -0,0 +1,25 @@
+-- This file is automatically generated. You should know what you did if you want to edit this
+-- !1 --
+1	2000-01-01
+
+-- !2 --
+1	2000-01-01
+
+-- !3 --
+1	2000-01-01
+
+-- !4 --
+1	2000-01-01
+
+-- !5 --
+1	2000-01-01
+
+-- !6 --
+1	2000-01-01
+
+-- !7 --
+
+-- !8 --
+
+-- !9 --
+

regression-test/suites/external_table_emr_p2/hive/test_hive_to_date.groovy

@@ -0,0 +1,49 @@
+// 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.
+
+suite("test_hive_to_date", "p2") {
+    String enabled = context.config.otherConfigs.get("enableExternalHiveTest")
+    if (enabled != null && enabled.equalsIgnoreCase("true")) {
+        String extHiveHmsHost = context.config.otherConfigs.get("extHiveHmsHost")
+        String extHiveHmsPort = context.config.otherConfigs.get("extHiveHmsPort")
+        String catalog_name = "test_hive_to_date"
+        sql """drop catalog if exists ${catalog_name};"""
+        sql """
+            create catalog if not exists ${catalog_name} properties (
+                'type'='hms',
+                'hadoop.username' = 'hadoop',
+                'hive.metastore.uris' = 'thrift://${extHiveHmsHost}:${extHiveHmsPort}'
+            );
+        """
+        logger.info("catalog " + catalog_name + " created")
+        sql """switch ${catalog_name};"""
+        logger.info("switched to catalog " + catalog_name)
+        sql """use multi_catalog;"""
+        sql """set enable_nereids_planner=true;"""
+        sql """set enable_fallback_to_original_planner=false"""
+        qt_1 "select * from datev2_csv"
+        qt_2 "select * from datev2_orc"
+        qt_3 "select * from datev2_parquet"
+        qt_4 "select * from datev2_csv where day>to_date(\"1999-01-01\")"
+        qt_5 "select * from datev2_orc where day>to_date(\"1999-01-01\")"
+        qt_6 "select * from datev2_parquet where day>to_date(\"1999-01-01\")"
+        qt_7 "select * from datev2_csv where day<to_date(\"1999-01-01\")"
+        qt_8 "select * from datev2_orc where day<to_date(\"1999-01-01\")"
+        qt_9 "select * from datev2_parquet where day<to_date(\"1999-01-01\")"
+    }
+}
+