diff --git a/association.go b/association.go
index 2f26b74a..62d638b6 100644
--- a/association.go
+++ b/association.go
@@ -30,27 +30,12 @@ func (association *Association) Find(value interface{}) *Association {
 func (association *Association) Append(values ...interface{}) *Association {
 	scope := association.Scope
 	field := association.Field
-	fieldType := field.Field.Type()
 
 	for _, value := range values {
-		reflectvalue := reflect.ValueOf(value)
-		if reflectvalue.Kind() == reflect.Ptr {
-			if reflectvalue.Elem().Kind() == reflect.Struct {
-				if fieldType.Elem().Kind() == reflect.Ptr {
-					field.Set(reflect.Append(field.Field, reflectvalue))
-				} else if fieldType.Elem().Kind() == reflect.Struct {
-					field.Set(reflect.Append(field.Field, reflectvalue.Elem()))
-				}
-			} else if reflectvalue.Elem().Kind() == reflect.Slice {
-				if fieldType.Elem().Kind() == reflect.Ptr {
-					field.Set(reflect.AppendSlice(field.Field, reflectvalue))
-				} else if fieldType.Elem().Kind() == reflect.Struct {
-					field.Set(reflect.AppendSlice(field.Field, reflectvalue.Elem()))
-				}
-			}
-		} else if reflectvalue.Kind() == reflect.Struct && fieldType.Elem().Kind() == reflect.Struct {
+		reflectvalue := reflect.Indirect(reflect.ValueOf(value))
+		if reflectvalue.Kind() == reflect.Struct {
 			field.Set(reflect.Append(field.Field, reflectvalue))
-		} else if reflectvalue.Kind() == reflect.Slice && fieldType.Elem() == reflectvalue.Type().Elem() {
+		} else if reflectvalue.Kind() == reflect.Slice {
 			field.Set(reflect.AppendSlice(field.Field, reflectvalue))
 		} else {
 			association.setErr(errors.New("invalid association type"))
@@ -65,23 +50,18 @@ func (association *Association) getPrimaryKeys(values ...interface{}) []interfac
 	scope := association.Scope
 
 	for _, value := range values {
-		reflectValue := reflect.ValueOf(value)
-		if reflectValue.Kind() == reflect.Ptr {
-			reflectValue = reflectValue.Elem()
-		}
+		reflectValue := reflect.Indirect(reflect.ValueOf(value))
 		if reflectValue.Kind() == reflect.Slice {
 			for i := 0; i < reflectValue.Len(); i++ {
-				newScope := scope.New(reflectValue.Index(i).Interface())
-				primaryKey := newScope.PrimaryKeyValue()
-				if !reflect.DeepEqual(reflect.ValueOf(primaryKey), reflect.Zero(reflect.ValueOf(primaryKey).Type())) {
-					primaryKeys = append(primaryKeys, primaryKey)
+				primaryField := scope.New(reflectValue.Index(i).Interface()).PrimaryKeyField()
+				if !primaryField.IsBlank {
+					primaryKeys = append(primaryKeys, primaryField.Field.Interface())
 				}
 			}
 		} else if reflectValue.Kind() == reflect.Struct {
-			newScope := scope.New(value)
-			primaryKey := newScope.PrimaryKeyValue()
-			if !reflect.DeepEqual(reflect.ValueOf(primaryKey), reflect.Zero(reflect.ValueOf(primaryKey).Type())) {
-				primaryKeys = append(primaryKeys, primaryKey)
+			primaryField := scope.New(value).PrimaryKeyField()
+			if !primaryField.IsBlank {
+				primaryKeys = append(primaryKeys, primaryField.Field.Interface())
 			}
 		}
 	}
@@ -121,16 +101,16 @@ func (association *Association) Replace(values ...interface{}) *Association {
 		newPrimaryKeys := association.getPrimaryKeys(field.Interface())
 
 		var addedPrimaryKeys = []interface{}{}
-		for _, new := range newPrimaryKeys {
+		for _, newKey := range newPrimaryKeys {
 			hasEqual := false
-			for _, old := range oldPrimaryKeys {
-				if reflect.DeepEqual(new, old) {
+			for _, oldKey := range oldPrimaryKeys {
+				if reflect.DeepEqual(newKey, oldKey) {
 					hasEqual = true
 					break
 				}
 			}
 			if !hasEqual {
-				addedPrimaryKeys = append(addedPrimaryKeys, new)
+				addedPrimaryKeys = append(addedPrimaryKeys, newKey)
 			}
 		}
 		for _, primaryKey := range association.getPrimaryKeys(values...) {