[SOLVED] Query problem

[whiskedaway]

I'm having a problem with my second query. I've included the PHP around it as it might help to see what I'm trying to do.

$sql = "SELECT quantity, sku FROM ItemsOrdered
	        WHERE orderID = '$_POST[orderID]'";
	$result = mysqli_query($cxn, $sql)
	          or die ("Couldn't execute query 1.");
	$rowname = mysqli_fetch_assoc($result);
        extract ($rowname);

	$sql2 = "UPDATE Stock SET quantity = (quantity + '$quantity')
	        WHERE sku = '$sku'";
	$result2 = mysqli_query($cxn, $sql2)
                  or die ("Couldn't execute query 2.");

Can someone see what the problem is? I think it has to do with the quantity = (quantity + '$quantity') part.

[rajivgonsalves]

what exactly is the problem, the query should be

 

$sql2 = "UPDATE Stock SET quantity = quantity + $quantity
              WHERE sku = '$sku'";

 

 

 

 

[whiskedaway]

I keep getting the error "Couldn't execute query 2." which is why I think there's a problem with my query 2 syntax. I've tried these four changes to the query:

 

$sql2 = "UPDATE Stock SET quantity = (quantity + '$quantity')
              WHERE sku = '$sku'";
$sql2 = "UPDATE Stock SET quantity = quantity + '$quantity'
              WHERE sku = '$sku'";
$sql2 = "UPDATE Stock SET quantity = quantity + $quantity
              WHERE sku = '$sku'";
$sql2 = "UPDATE Stock SET quantity = (quantity + $quantity)
              WHERE sku = '$sku'";

 

It just won't work at all. The only other thing I can think of is that maybe the PHP before it is wrong, but I can't see an error in that either.

[rajivgonsalves]

please change this

 

$result2 = mysqli_query($cxn, $sql2)
                  or die ("Couldn't execute query 2.");

 

to

$result2 = mysqli_query($cxn, $sql2)
                  or die ("Couldn't execute query 2:".mysql_error());

 

for a better error description once you done that you should have the exact error and it will enable us to debug your code

[whiskedaway]

Unfortunately, that hasn't yielded any results:

 

Couldn't execute query 2:

 

If you want to have a look at it yourself, it's up at http://www.caitlin-helbig.com/adelaidebooks/receipt.php and you can use an orderID of 00000001.

[rajivgonsalves]

actually thats because of my faulty code it should have been mysqli_error() instead of mysql_error()

[whiskedaway]

Oh, I didn't even notice that. Here's the output:

 

Warning: mysqli_error() expects exactly 1 parameter, 0 given in /home/nabira/chelbig/adelaidebooks/receipt.php on line 23

Couldn't execute query 2.

 

Line 23 is:

or die ("Couldn't execute query 2.".mysqli_error());

[rajivgonsalves]

hmm.. Yeah you will have to specify your link identifyer as a paramater

[whiskedaway]

Sorry, I don't get what you mean.

[rajivgonsalves]

it should have been mysqli_error($cxn)

[whiskedaway]

Oh gotcha. Here's the new error message:

 

Couldn't execute query 2. Unknown column 'quantity' in 'field list'.

 

And I think I just figured it out myself. The column is named quantity in ItemsOrdered, but it's quantityOnHand in Stock. Gah.

 

Thanks so much for your help, I can't believe I made such a stupid error.

[rajivgonsalves]

Well we all make these mistakes, you can save alot of time if you have more descriptive error messages in your code that would pinpoint the problem right away