SELECT * FROM table WHERE kol_vo <> 0 ORDER BY RAND()foreach($results as $result) {
echo $result['zak'];
// Выполняем запрос обновления
UPDATE table SET kol_vo = kol_vo - 1 WHERE id = $result['id'];
}
UPDATE tabla SET kol_vo = kol_vo - 1 WHERE id = $result'id'