Updating SQL if item exists

[petenaylor]

Hi all

 

I am trying to write a piece of code that cheks to see if an item is in the SQL databse and updates the quantity if it is, or adds it as a new line if it isn't. Here's my code:

 

 

if (isset($_GET['add'])) {

$id = $_GET['id'];
$qty = $_GET['qty'];

$date = date ('D M j G:i:s');

$sql_products = mysql_query("SELECT * FROM `items` WHERE `id` = '".$id."'");
$result_products = mysql_fetch_array($sql_products);
$product_title = $result_products['title'];
$product_price = $result_products['price'];


$sql_inbasket = mysql_query("SELECT * FROM `store_basket` WHERE `id` = '".$id."' AND sessionid = '".$sessionid."'");
$isiteminbasket = mysql_num_rows($sql_inbasket);

if ($isiteminbasket == 0) {

mysql_query ("INSERT INTO `store_basket` SET sessionid = '".$sessionid."', productid = '".$id."', 

item = '".$product_title."', qty = '".$qty."', price = '".$product_price."', date = '".$date."'");

header("Location: basket.php");	

}

else {

mysql_query("UPDATE `store_basket` SET qty = qty + 1 WHERE id = '".$id."' AND sessionid = '".$sessionid."'") ; 

header("Location: basket.php");		
}
}

 

Every time I try and add the same item to the basket, it adds as a new line instead of updating the existing line.

 

Many thanks for your help!

 

Pete

[Maq]

Please, use the

tags in the future.