public function cmdDeleteFieldValue()
    {
        $id = $this->getParam(0);

        if (empty($id) || !is_numeric($id)) {
            $this->errorAndExit($this->text('Invalid command'));
        }

        if ($this->getParam('field')) {
            $deleted = $count = 0;
            foreach ($this->field_value->getList(array('field_id' => $id)) as $item) {
                $count++;
                $deleted += (int) $this->field_value->delete($item['field_value_id']);
            }

            $result = $count && $count == $deleted;

        } else {
            $result = $this->field_value->delete($id);
        }

        if (empty($result)) {
            $this->errorAndExit($this->text('Unexpected result'));
        }

        $this->output();
    }