public function andNotIn($key, array $values)
    {
        if ($values) {
            $value = sprintf('%s NOT IN (%s)', $key, join(', ', array_fill(0, count($values), '?')));
            return $this->andAdd($value, $values);
        } else {
            $value = '1';
            return $this->andAdd($value, $values);
        }
    }