Hello

I have two arrays with data that relates directly to each other.
Key 0 in the first array relates to key 0 in the second and so on.

Array1 ( [0] => 4 [1] => 9 [2] => 12 [3] => 16 [4] => 18 [5] => 20 )
Array2 ( [0] => 1 [1] => 3 [2] => 1 [3] => 1 [4] => 1 [5] => 2 )

I need a way to loop through these arrays in order to add/subtract amounts stored in a database. Array1 is the product id and Array 2 is the amount.

What is the best way of doing this?


Thanks in advance.

This'll do what you want dave;

PHP Code:


// script controller

if(isset($_POST['Submit']))
{

// count number of indexes in array1 and set limit

$limit = count($Array1);

// begin loop through array1

for ($i=0; $I<$limit; $i++)

{

//get adjustment amt from array2

$adjustAmt = $Array2[$i];

// select product 'Amount' from db

$sql = 'SELECT Amount FROM table_gifts WHERE product_ID = '.$Array[$i];
$query = mysql_query($sql, $dbConn) or die(mysql_error());

// get amount from resultset

$amount = mysql_fetch_assoc['Amount'];

// do calc

$updateAmt = $amount + $adjustAmt;

// update amount

$sql2 = 'UPDATE table_gifts SET Amount = '.$updateAmt.' WHERE product_ID = '.$Array1[$i];
$query2 = mysql_query($sql2, $dbConn) or die (mysql_error());

// end for loop

}

// redirect after successful updates

$redirect = 'someURL.php?updates=ok';
header('Location: '.$redirect);
exit();

// end script controller

} 


Cheers, played around with the code a bit...........works well now.
Slowly getting my head around arrays!

Dave, I'd split the time you have for learning PHP to include learning SQL for MySql as well. Quite often, fairly complex manoevers in php are done very simply in sql. For example, the above update query could have had mysql do the arithmetic instead of php.

Dave, I'd split the time you have for learning PHP to include learning SQL for MySql as well. Quite often, fairly complex manoevers in php are done very simply in sql. For example, the above update query could have had mysql do the arithmetic instead of php.

I'm glad you got it working, I didn't see the "$I" typo, that woulda thrown an undefined notice and screwed up the loop.