diff --git a/FreeSql.Tests/FreeSql.Tests/UnitTest3.cs b/FreeSql.Tests/FreeSql.Tests/UnitTest3.cs
index ee8ef69de..36f6ae2a9 100644
--- a/FreeSql.Tests/FreeSql.Tests/UnitTest3.cs
+++ b/FreeSql.Tests/FreeSql.Tests/UnitTest3.cs
@@ -84,6 +84,17 @@ public void Test03()
 
             fsql = ib.Get("db3");
             fsql.Select<ut3_t1>().Limit(10).ToList();
+
+            fsql = g.sqlserver;
+            fsql.Insert<OrderMain>(new OrderMain { OrderNo = "1001", OrderTime = new DateTime(2019, 12, 01) }).ExecuteAffrows();
+            fsql.Insert<OrderDetail>(new OrderDetail { OrderNo = "1001", ItemNo = "I001", Qty = 1 }).ExecuteAffrows();
+            fsql.Insert<OrderDetail>(new OrderDetail { OrderNo = "1001", ItemNo = "I002", Qty = 1 }).ExecuteAffrows();
+            fsql.Insert<OrderDetail>(new OrderDetail { OrderNo = "1001", ItemNo = "I003", Qty = 1 }).ExecuteAffrows();
+            fsql.Insert<OrderMain>(new OrderMain { OrderNo = "1002", OrderTime = new DateTime(2019, 12, 02) }).ExecuteAffrows();
+            fsql.Insert<OrderDetail>(new OrderDetail { OrderNo = "1002", ItemNo = "I011", Qty = 1 }).ExecuteAffrows();
+            fsql.Insert<OrderDetail>(new OrderDetail { OrderNo = "1002", ItemNo = "I012", Qty = 1 }).ExecuteAffrows();
+            fsql.Insert<OrderDetail>(new OrderDetail { OrderNo = "1002", ItemNo = "I013", Qty = 1 }).ExecuteAffrows();
+            fsql.Ado.Query<object>("select * from orderdetail left join ordermain on orderdetail.orderno=ordermain.orderno where ordermain.orderno='1001'");
         }
 
         class TestByte
@@ -106,6 +117,19 @@ class ut3_t2
             public int id { get; set; }
             public string name { get; set; }
         }
+
+        public class OrderMain
+        {
+            public string OrderNo { get; set; }
+            public DateTime OrderTime { get; set; }
+            public decimal Amount { get; set; }
+        }
+        public class OrderDetail
+        {
+            public string OrderNo { get; set; }
+            public string ItemNo { get; set; }
+            public decimal Qty { get; set; }
+        }
     }
 
 }
diff --git a/FreeSql/Internal/UtilsExpressionTree.cs b/FreeSql/Internal/UtilsExpressionTree.cs
index 8c8631c1e..b35b342f6 100644
--- a/FreeSql/Internal/UtilsExpressionTree.cs
+++ b/FreeSql/Internal/UtilsExpressionTree.cs
@@ -1331,8 +1331,12 @@ internal static RowInfo ExecuteArrayRowReadClassOrTuple(string flagStr, Type typ
                             var expandodic = new Dictionary<string, object>();// (IDictionary<string, object>)expando;
                             var fc = row2.FieldCount;
                             for (var a = 0; a < fc; a++)
-                                //expando[row2.GetName(a)] = row2.GetValue(a);
-                                expandodic.Add(row2.GetName(a), row2.GetValue(a));
+                            {
+                                var name = row2.GetName(a);
+                                //expando[name] = row2.GetValue(a);
+                                if (expandodic.ContainsKey(name)) continue;
+                                expandodic.Add(name, row2.GetValue(a));
+                            }
                             //expando = expandodic;
                             return new RowInfo(expandodic, fc);
                         };