opt between

fe/fe-core/src/main/java/org/apache/doris/nereids/parser/LogicalPlanBuilder.java

@@ -3495,10 +3495,16 @@ private Expression withPredicate(Expression valueExpression, PredicateContext ct
             Expression outExpression;
             switch (ctx.kind.getType()) {
                 case DorisParser.BETWEEN:
-                    outExpression = new And(
-                            new GreaterThanEqual(valueExpression, getExpression(ctx.lower)),
-                            new LessThanEqual(valueExpression, getExpression(ctx.upper))
-                    );
+                    Expression lower = getExpression(ctx.lower);
+                    Expression upper = getExpression(ctx.upper);
+                    if (lower.equals(upper)) {
+                        outExpression = new EqualTo(valueExpression, lower);
+                    } else {
+                        outExpression = new And(
+                                new GreaterThanEqual(valueExpression, getExpression(ctx.lower)),
+                                new LessThanEqual(valueExpression, getExpression(ctx.upper))
+                        );
+                    }
                     break;
                 case DorisParser.LIKE:
                     outExpression = new Like(

fe/fe-core/src/test/java/org/apache/doris/nereids/parser/BetweenTest.java

@@ -0,0 +1,40 @@
+// 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.parser;
+
+import org.apache.doris.nereids.trees.expressions.And;
+import org.apache.doris.nereids.trees.expressions.EqualTo;
+import org.apache.doris.nereids.trees.expressions.Expression;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class BetweenTest {
+    private static final NereidsParser PARSER = new NereidsParser();
+
+    @Test
+    public void testBetween() {
+        String expression ="A between 1 and 1"; //
+        Expression result = PARSER.parseExpression(expression);
+        Assertions.assertInstanceOf(EqualTo.class, result);
+
+        expression = "A between 1 and 2";
+        result = PARSER.parseExpression(expression);
+        Assertions.assertInstanceOf(And.class, result);
+    }
+}