[fix](DECIMALV3) Fix the error in DECIMALV3 when explicitly casting. (#19926)

before

mysql [test]>select cast(1 as DECIMALV3(16, 2)) /  cast(3 as DECIMALV3(16, 2));
+-----------------------------------------------------------+
| CAST(1 AS DECIMALV3(16, 2)) / CAST(3 AS DECIMALV3(16, 2)) |
+-----------------------------------------------------------+
|                                                      0.00 |
+-----------------------------------------------------------+


mysql [test]>select * from divtest;
+------+------+
| id   | val  |
+------+------+
|    3 | 5.00 |
|    2 | 4.00 |
|    1 | 3.00 |
+------+------+

mysql [test]>select cast(1 as decimalv3(16,2)) / val from divtest;
+-------------------------------------+
| CAST(1 AS DECIMALV3(16, 2)) / `val` |
+-------------------------------------+
|                                   0 |
|                                   0 |
|                                   0 |
+-------------------------------------+
after

mysql [test]>select cast(1 as DECIMALV3(16, 2)) /  cast(3 as DECIMALV3(16, 2));
+-----------------------------------------------------------+
| CAST(1 AS DECIMALV3(16, 2)) / CAST(3 AS DECIMALV3(16, 2)) |
+-----------------------------------------------------------+
|                                                      0.33 |
+-----------------------------------------------------------+

mysql [test]>select cast(1 as decimalv3(16,2)) / val from divtest;
+-------------------------------------+
| CAST(1 AS DECIMALV3(16, 2)) / `val` |
+-------------------------------------+
|                            0.250000 |
|                            0.200000 |
|                            0.333333 |
+-------------------------------------+
This is because in the previous code, the constant 1.000 would be transformed into 1.

remove "ReduceType

fe/fe-core/src/main/java/org/apache/doris/analysis/ArithmeticExpr.java

@@ -543,11 +543,6 @@ public class ArithmeticExpr extends Expr {
     @Override
     public void analyzeImpl(Analyzer analyzer) throws AnalysisException {
         if (VectorizedUtil.isVectorized()) {
-            for (Expr child : children) {
-                if (child instanceof DecimalLiteral && child.getType().isDecimalV3()) {
-                    ((DecimalLiteral) child).tryToReduceType();
-                }
-            }
             // bitnot is the only unary op, deal with it here
             if (op == Operator.BITNOT) {
                 Type t = getChild(0).getType();

regression-test/data/correctness/test_cast_as_decimalv3.out

@@ -0,0 +1,9 @@
+-- This file is automatically generated. You should know what you did if you want to edit this
+-- !select1 --
+0.33333333
+0.25000000
+0.20000000
+
+-- !select2 --
+0.33
+

regression-test/data/decimalv3/tpch_sf0.1_p1/sql/q14.out

@@ -1,4 +1,4 @@
 -- This file is automatically generated. You should know what you did if you want to edit this
 -- !q14 --
-16.2838
+16.283855
 

regression-test/suites/correctness/test_cast_as_decimalv3.groovy

@@ -0,0 +1,50 @@
+// 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_cast_as_decimalv3") {
+     sql """ DROP TABLE IF EXISTS divtest """
+     sql """
+        CREATE TABLE IF NOT EXISTS divtest (
+            `id` int(11) ,
+            `val` decimalv3(16,2) 
+        )
+        UNIQUE KEY(`id`)
+        DISTRIBUTED BY HASH(`id`) BUCKETS 10
+        PROPERTIES (
+        "enable_unique_key_merge_on_write" = "true",
+        "replication_num" = "1"
+        );
+    """
+    sql """
+        set enable_nereids_planner=false,enable_fold_constant_by_be = false
+    """
+    sql """
+        INSERT INTO divtest VALUES(1,3.00)
+    """
+    sql """
+        INSERT INTO divtest VALUES(2,4.00)
+    """
+    sql """
+        INSERT INTO divtest VALUES(3,5.00)
+    """
+    qt_select1 """
+        select cast(1 as decimalv3(16,2)) / val from divtest order by id
+    """
+    qt_select2 """
+        select cast(1 as DECIMALV3(16, 2)) /  cast(3 as DECIMALV3(16, 2))
+    """ 
+}