Use Association mode

orm/group.go

@@ -120,6 +120,18 @@ func UpdateGroup(args map[string]string, r *http.Request) (IDer, error) {
 	if err != nil {
 		return nil, err
 	}
+
+	log.Println("After decoding...", group.(*Group).TeacherIDs)
+	// _, err = SaveGroup(group)
+	// if err != nil {
+	// 	return nil, err
+
+	// }
+
+	if err := DB().Debug().Model(group).Association("Teachers").Replace(group.(*Group).Teachers).Error; err != nil {
+		return nil, err
+	}
+
 	group, err = GetGroup(args)
 	if err != nil {
 		return nil, err