diff --git a/mapping.go b/mapping.go
index 6d2d32b..0ec0796 100644
--- a/mapping.go
+++ b/mapping.go
@@ -65,7 +65,7 @@ func (b *Mapper) extractStructData(data ...any) (map[string][]*TableRowMateria,
 			}
 
 			if tableName == "" {
-				return nil, fmt.Errorf("not import TableName() string func for struct type: %s", uniqueTypeName)
+				return nil, fmt.Errorf("not func TableName() string func for struct type: %s", uniqueTypeName)
 			}
 		}
 
diff --git a/mapping_test.go b/mapping_test.go
index 4e75f70..1ecefde 100644
--- a/mapping_test.go
+++ b/mapping_test.go
@@ -58,7 +58,7 @@ func TestBuilderInsert(t *testing.T) {
 			Ts:      time.Now(), LoadUnitId: "负载单体ID", PInt: &p, NullInt32: sql.NullInt32{Int32: 32, Valid: true},
 		},
 		&TaosUser{
-			TaosTAG: &TaosTAG{DevId: "User001", DevType: "User类型", DataType: "User数据类型001"},
+			TaosTAG: &TaosTAG{DevId: "User001", DevType: "User类型", DataType: "User数据类型001", Alias: "三儿"},
 			Ts:      time.Now(), Name: "张三",
 		}, &TaosUser{
 			TaosTAG: &TaosTAG{DevId: "User002", DevType: "User类型", DataType: "User数据类型002"},
diff --git a/scan.go b/scan.go
index eb93511..d394d3d 100644
--- a/scan.go
+++ b/scan.go
@@ -81,7 +81,11 @@ func scan(data interface{}) (*StructMate, error) {
 			continue
 		}
 
-		sr.Field2IndexCache[field.Name] = append(sr.Field2IndexCache[field.Name], i)
+		if len(sr.Field2IndexCache[field.Name]) > 0 {
+			return nil, fmt.Errorf("duplicate field [%s %s `db:%s`]", field.Name, field.Type.Name(), columnName)
+		}
+
+		sr.Field2IndexCache[field.Name] = append([]int{}, i)
 		sr.DBName2IndexCache[columnName] = append(sr.DBName2IndexCache[columnName], i)
 		sr.Filed2DBNameCache[field.Name] = columnName