commit 043064a3d751c4042d6060d03bef819ce93772f2
Author: Christian Ehringfeld <c.ehringfeld@mailbox.org>
Date:   Sat Jul 14 16:07:33 2018 +0200

    closes #645

diff --git a/src/entitymanager.h b/src/entitymanager.h
index 578a781..2096e8c 100644
--- a/src/entitymanager.h
+++ b/src/entitymanager.h
@@ -238,7 +238,7 @@ class EntityManager : public QObject {
     template<typename T>
     void refresh(QSharedPointer<T> entity, const bool resolveRelations = true) {
         static_assert(std::is_base_of<Entity, T>::value, "T must inherit from Entity");
-        if(entity) {
+        if(entity && entity->getId() > -1) {
             auto map  = this->findByPk(entity->getId(), entity);
             QSharedPointer<Entity> e = entity;
             Converter c = Converter();