How to understand entities, save, hasChanged

Thank you Kenjis.

It now works.

Something like this right? It now saves on new data, updates and doesnt do anthing if the record is not changed.

PHP Code:

foreach ($aa_winter_sports_points->features as $aa_winter_sports_point ){
        
            // Convert stdClass object to associative array in php
            // https://stackoverflow.com/questions/34428702/convert-stdclass-object-to-associative-array-in-php
            $data = array($aa_winter_sports_point->properties);
            $new_fill = json_decode(json_encode($data[0]), TRUE);
            
            // find() will return an entity $existing_data.  Works also in findAll();
            $QgisResort = $this->QgisSkiResortModel->find($new_fill['id']);
            
            //get list all permissable attributes that can go into the db
            $attributes = $this->QgisSkiResortModel->allowedFields;
           
            // filter new attributes in the new fill
            $attributes_matching_from_new_fill = array_filter($new_fill, function ($value, $key) use ($attributes) {
                if (in_array($key, $attributes)) {
                  return true;
                }
            }, ARRAY_FILTER_USE_BOTH);
            
            // create a new record
            if ($QgisResort === null){
                $newSkiResort = new \App\Entities\QgisSkiResortEntity();
                $newSkiResort->fill($attributes_matching_from_new_fill);
                $this->QgisSkiResortModel->save($newSkiResort);
                $resortNew++;
            // record exists
            } elseif($QgisResort){
                $QgisResort->fill($attributes_matching_from_new_fill);
                if ($QgisResort->hasChanged()){
                    if ($this->QgisSkiResortModel->save($attributes_matching_from_new_fill)){
                        $resortUpdated++;   
                    }
                }
                if (!$QgisResort->hasChanged()){
                    $resortNothingToUpdate++;
                    echo $QgisResort->id.'</br>';
                    echo $QgisResort->{'name:en'}.'</br>';
                    echo '</br>';
                }
            }
            
            $i++;
        }