Change_Item::prepareInputForAdd PHP Method

    function prepareInputForAdd($input)
    {
        // Well, if I remember my PHP: empty(0) == true ...
        if (empty($input['changes_id']) || $input['changes_id'] == 0) {
            return false;
        }
        // Avoid duplicate entry
        if (countElementsInTable($this->getTable(), ['changes_id' => $input['changes_id'], 'itemtype' => $input['itemtype'], 'items_id' => $input['items_id']]) > 0) {
            return false;
        }
        return parent::prepareInputForAdd($input);
    }