diff --git a/Src/Asp.NetCore2/AccessTest/Unit/UnitInsertNavN.cs b/Src/Asp.NetCore2/AccessTest/Unit/UnitInsertNavN.cs
new file mode 100644
index 000000000..b34087326
--- /dev/null
+++ b/Src/Asp.NetCore2/AccessTest/Unit/UnitInsertNavN.cs
@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using SqlSugar;
+namespace OrmTest
+{
+    public class UnitInsertNavN
+    {
+        public static void Init()
+        {
+            //导航更新问题
+            //关联层级大于或等于四层时 存在脏数据
+
+            Console.WriteLine("----------程序开始----------");
+
+            //创建数据库对象
+            SqlSugarClient db = new SqlSugarClient(new ConnectionConfig()
+            {
+                ConnectionString = Config.ConnectionString,//Master Connection
+                DbType = DbType.Access,
+                InitKeyType = InitKeyType.Attribute,
+                IsAutoCloseConnection = true 
+            });
+            db.Aop.OnLogExecuting = (sql, pars) =>
+            {
+                Console.WriteLine(UtilMethods.GetSqlString(db.CurrentConnectionConfig.DbType,sql,pars));//输出sql,查看执行sql 性能无影响
+            };
+
+            //如果不存在创建数据库存在不会重复创建
+            //db.DbMaintenance.CreateDatabase();
+            //根据实体名创建对应表
+            db.CodeFirst.InitTables(typeof(ClassA), typeof(ClassB));
+ 
+            //清空表中数据
+            db.Deleteable<ClassA>().ExecuteCommand();
+            db.Deleteable<ClassB>().ExecuteCommand(); 
+
+            //初始化数据 共四层 都是一对多的关系表
+            ClassA a = new ClassA();
+            a.AId =1;
+            a.UpdateTime= DateTime.Now;
+         
+            ClassB b = new ClassB();
+            b.BId = 2;
+            b.AId = a.AId;
+            a.B = new List<ClassB>() { b };
+
+
+          //导航插入四表数据
+          db.InsertNav(a)
+                .Include(t => t.B) 
+                .ExecuteCommand();
+
+            var list= db.Queryable<ClassA>().ToList();
+            var list2=db.Queryable<ClassA>().Includes(z => z.B).ToList();
+            if (list2.Count == 0) 
+            {
+                throw new Exception("unit error");
+            }
+            Console.WriteLine("----------程序结束----------");
+
+        }
+
+        /// <summary>
+        /// 一级类
+        /// </summary>
+        [SugarTable("tb_a1")]
+        public class ClassA
+        {
+            [SugarColumn(IsPrimaryKey = true,IsIdentity =true)]
+            public int AId { get; set; }
+            [Navigate(NavigateType.OneToMany, nameof(ClassB.AId))]
+            public List<ClassB> B { get; set; }
+            [SugarColumn(IsNullable = true)]
+            public DateTime? UpdateTime { get; set; }
+        }
+        /// <summary>
+        /// 二级类
+        /// </summary>
+        [SugarTable("tb_b2")]
+        public class ClassB
+        {
+            [SugarColumn(IsPrimaryKey = true, IsIdentity = true)]
+            public int BId { get; set; }
+            public int AId { get; set; }
+          
+        }
+       
+    }
+}
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