[HUDI-2319] dbt example models to demonstrate hudi dbt integration (#5220)

* dbt example models to demonstrate hudi dbt integration

* Fixed readme text

hudi-examples/hudi-examples-dbt/models/example/hudi_insert_overwrite_table.sql

@@ -0,0 +1,37 @@
+/*
+ * 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.
+ *
+ */
+
+/*
+ Example of an insert_overwrite for a non-partitioned table with incremental materialization.
+ */
+{{ config(
+    materialized='incremental',
+    file_format='hudi',
+    incremental_strategy='insert_overwrite',
+    options={
+        'type': 'cow',
+        'precombineKey': 'ts',
+    },
+    unique_key='id'
+   )
+}}
+
+select id, cast(rand() as string) as name, current_timestamp() as ts
+from {{ ref('hudi_insert_table') }}