<?php
$article_title = $_POST['article_title'];
$article_titleid = $_POST['article_titleid'];
$connect = new mysqli("host", "user", "pasword", "bdname");
if($connect->query("update tovar set
article_title = '$article_title'
where
id = '$article_titleid'"))
echo "OK";
else
echo "ОШИБКА В ЗАПРОСЕ!";
?>