如何使用php更新mysql中的多个列

Here i am trying to update update multiple column values in mysql table using php.

$product_id = mysqli_real_escape_string($link, $_POST['product_id']);
$product_name = mysqli_real_escape_string($link, $_POST['product_name']);
$product_category = mysqli_real_escape_string($link, $_POST['product_category']);

$sql = "UPDATE product_list (product_name, product_category, product_price,product_description,product_size_category) VALUES ('$product_name', '$product_category', '$product_price', '$product_description', '$size_category')";
}"

我有 5 个列值要在表中更新，我正在使用变量来保存数据并使用该变量想要更新表中的值我该怎么做?

 $sql = "UPDATE `product_list` SET 
       `product_name` = '$product_name', 
       `product_category` = '$product_category', 
       `product_price` = '$product_price', 
       `product_description` = '$product_description', 
       `product_size_category` = '$size_category' 
  where clause..... (if required) ";