Add values from a row from a database

ec2m

I have this code (yes I'm really a newbie)

<?php do {

echo $row_numbers['numb']; ?><br />

<?php } while ($row_numbers = mysql_fetch_assoc($numbers));

mysql_free_result($numbers);
?>

I want to add or get the sum the values $row_numbers['numb'] so add together

I know there's a simple answer I just cant get my head round it, I've tried a few different things. many thanks peeps

johanafm

First off, you have an issue with your php code. Furthermore, your code is hard to read. And do wrap it in php tags when posting, that is [ php] and [/code]

First, a step up in readability

<?php
// The first time this loop is run, $row_numbers is not set. Will cause an error
do {
	// indenting code is awesome
	echo $row_numbers['numb'];

?>
Keeping php opening and closing tags on their own rows makes them easier to see.
<br />
<?php 
} while ($row_numbers = mysql_fetch_assoc($numbers));

So, let's fix the issues and get rid of one set of <?php ?>


[code=php]
<?php
// doing it like this means $row_numbers is set the first time as well
while ($row_numbers = mysql_fetch_assoc($numbers)) {
	// adding the <br/> here means you don't have to drop out of php parse mode
	echo $row_numbers['numb'] . '<br/>';
}
?>

And finally, to get the sum you want

<?php
// initialize $sum to 0 before the loop
$sum = 0;

while ($row_numbers = mysql_fetch_assoc($numbers)) {
	// adding the <br/> here means you don't have to drop out of php parse mode
	echo $row_numbers['numb'] . '<br/>';
	// add $row_numbers['numb'] to $sum. cast to int before adding.
	$um += (int) $row_numbers['numb'];
}
?>

ec2m

Thanks very much johanafm, I have this code now which seems to work and ads up the visible values, but it ignores the first record in the database, its really weird, I've just tried changing the values in the database but it seems to have no effect and always misses out the first record:

<?php 
$sum = 0;
// doing it like this means $row_numbers is set the first time as well 
while ($row_numbers = mysql_fetch_assoc($numbers)) { 
    // adding the <br/> here means you don't have to drop out of php parse mode 
    echo $row_numbers['numb'] . '<br/>';
	$sum += (int) $row_numbers['numb']; 
} 
?>


<br />

<?php 

echo $sum;


?>

djjjozsi

Or you can use the SUM() function in mysql:

SELECT SUM(numb) from table

and you can get the sum of that field in one query.

ec2m

It works if you do:

[ php ]
<?php
$sum = $row_numbers;
// doing it like this means $row_numbers is set the first time as well
while ($row_numbers = mysql_fetch_assoc($numbers)) {
// adding the <br/> here means you don't have to drop out of php parse mode
echo $row_numbers['numb'] . '<br/>';
$sum += (int) $row_numbers['numb'];
}
?>

<br />

<?php

echo $sum;

[ /php ]

johanafm

If you miss the first record, then you must have a call to one of the mysql_fetch functions before the while loop, which would also mean your do..while loop worked. Simply remove the first mysql_fetch call (on this result set).

Ashley_Sheridan

I assume your content is already in an array, and not necessarily coming from a database. In that case, you can use array_sum() on the array to sum the values from it.

Weedpacket

Conversely, if the numbers are the only things you're retrieving, and only for the purpose of summing them, then a SELECT SUM query would be a much cleaner approach.