diff --git a/dbHandler.go b/dbHandler.go
index fc5bd95..8a301dc 100644
--- a/dbHandler.go
+++ b/dbHandler.go
@@ -129,12 +129,12 @@ func (dH *DBHandler) AddNewColum(model any) error {
 //
 // Returns:
 //   - error: Any query error or “not found” message.
-func (dH *DBHandler) GetById(model any, relation string, id uint) (err error) {
+func (dH *DBHandler) GetById(model any, id uint, relations ...string) (err error) {
 	dH.logger.Debug("getById", "find id "+fmt.Sprint(id))
 
 	query := dH.db
 
-	if relation != "" {
+	for _, relation := range relations {
 		query = query.Preload(relation)
 	}
 
@@ -170,10 +170,10 @@ func (dH *DBHandler) GetById(model any, relation string, id uint) (err error) {
 //
 // Returns:
 //   - error: Any database query error.
-func (dH *DBHandler) GetByKey(model any, relation string, key string, value any, LikeSearch bool) error {
+func (dH *DBHandler) GetByKey(model any, key string, value any, LikeSearch bool, relations ...string) error {
 	query := dH.db
 
-	if relation != "" {
+	for _, relation := range relations {
 		query = query.Preload(relation)
 	}
 	if LikeSearch {
@@ -203,22 +203,26 @@ func (dH *DBHandler) GetByKey(model any, relation string, key string, value any,
 //
 // Returns:
 //   - error: If the model is invalid or query/update fails.
-func (dH *DBHandler) UpdateValuesById(model any, relation string, id uint) error {
-	dH.logger.Debug("updateValuesById", "model"+fmt.Sprint(model))
+func (dH *DBHandler) UpdateValuesById(model any, id uint, relations ...string) error {
+	dH.logger.Debug("updateValuesByKey", "model"+fmt.Sprint(model))
+
 	modelType := reflect.TypeOf(model)
 	if modelType.Kind() != reflect.Ptr {
 		return errors.New("model must be a pointer to struct")
 	}
 
 	lookUpModel := reflect.New(modelType.Elem()).Interface()
-	if err := dH.GetById(lookUpModel, relation, id); err != nil {
+	if err := dH.GetById(lookUpModel, id, relations...); err != nil {
 		return err
 	}
-	query := dH.db
 
-	if relation != "" {
+	// Preload relations
+	query := dH.db
+	for _, relation := range relations {
 		query = query.Preload(relation)
 	}
+
+	// Update only provided keys
 	return query.Model(lookUpModel).Updates(model).Error
 }
 
@@ -240,7 +244,7 @@ func (dH *DBHandler) UpdateValuesById(model any, relation string, id uint) error
 //
 // Returns:
 //   - error: Any query or update error.
-func (dH *DBHandler) UpdateValuesByKey(model any, relation string, key string, value any) error {
+func (dH *DBHandler) UpdateValuesByKey(model any, key string, value any, relations ...string) error {
 	dH.logger.Debug("updateValuesByKey", "model"+fmt.Sprint(model))
 	modelType := reflect.TypeOf(model)
 	if modelType.Kind() != reflect.Ptr {
@@ -248,13 +252,13 @@ func (dH *DBHandler) UpdateValuesByKey(model any, relation string, key string, v
 	}
 
 	lookUpModel := reflect.New(modelType.Elem()).Interface()
-	if err := dH.GetByKey(lookUpModel, "", key, value, false); err != nil {
+	if err := dH.GetByKey(lookUpModel, key, value, false, relations...); err != nil {
 		return err
 	}
 
 	query := dH.db
 
-	if relation != "" {
+	for _, relation := range relations {
 		query = query.Preload(relation)
 	}
 	return query.Model(lookUpModel).Updates(model).Error
@@ -267,19 +271,13 @@ func (dH *DBHandler) DeleteById(model any, relation string, ids ...uint) error {
 
 	if len(ids) == 1 && ids[0] == 0 {
 		dH.logger.Debug("deleteById", "delete ALL records!")
-		return dH.db.Session(&gorm.Session{AllowGlobalUpdate: true}).
+		return dH.db.Session(&gorm.Session{AllowGlobalUpdate: true, FullSaveAssociations: true}).
 			Delete(model).Error
 	}
 
 	dH.logger.Debug("deleteById", "delete ids "+fmt.Sprint(ids))
 
-	query := dH.db
-
-	if relation != "" {
-		query = query.Preload(relation)
-	}
-
-	if err := query.Delete(model, ids).Error; err != nil {
+	if err := dH.db.Delete(model, ids).Error; err != nil {
 		return fmt.Errorf("delete failed: %w", err)
 	}
 	return nil
@@ -302,7 +300,7 @@ func (dH *DBHandler) DeleteById(model any, relation string, ids ...uint) error {
 //
 // Returns:
 //   - error: Any deletion error.
-func (dH *DBHandler) DeleteByKey(model any, relation string, key string, value any, LikeSearch bool) error {
+func (dH *DBHandler) DeleteByKey(model any, key string, value any, LikeSearch bool, relations ...string) error {
 	if LikeSearch {
 		value = strings.ReplaceAll(fmt.Sprint(value), "*", "%")
 		dH.logger.Debug("deleteByKey", "delete like key "+key+" value "+fmt.Sprint(value))
@@ -313,14 +311,14 @@ func (dH *DBHandler) DeleteByKey(model any, relation string, key string, value a
 
 	query := dH.db
 
-	if relation != "" {
+	for _, relation := range relations {
 		query = query.Preload(relation)
 	}
 
 	return query.Where(key+" = ?", value).Delete(model).Error
 }
 
-func (dH *DBHandler) Exists(model any, relation string, key string, value any, likeSearch bool) (found bool) {
+func (dH *DBHandler) Exists(model any, key string, value any, likeSearch bool, relations ...string) (found bool) {
 	var query string
 	var args any
 
@@ -350,7 +348,7 @@ func (dH *DBHandler) Exists(model any, relation string, key string, value any, l
 	dH.logger.Debug("exists", "checking existence for key "+query+" value "+fmt.Sprint(args))
 
 	datababase := dH.db
-	if relation != "" {
+	for _, relation := range relations {
 		datababase = datababase.Preload(relation)
 	}