MySQL SUM to PHP While Loop - php

Question

I am not sure how to get the result of a Mysql SUM into your while loop THEN into a variable for displaying in an HTML table.
Firstly I pass a list of codes ie ("1111", "33311", "43433") to a HTML form textarea then implode those codes into a variable called $in. I then pass the list of codes (represented by $in) to my SQL Query.
Mysql Query
SELECT tbl1.code, tbl1.name, tbl1.cost, tble.price, tbl1.vat, sum(tbl2.onhand) as onhand
FROM tbl1
INNER JOIN tbl2 ON tbl1.code=tbl2.code
WHERE (tbl2.name='AC' OR tbl2.name='WH')
AND tbl1.code IN ($in)
NOTE The query works if I do this instead (without the SUM and brackets) BUT it still shows an empty table cell for $stock:
tbl1.vat, tbl2.onhand AS onhand
I am then attempting to pass the value of the Mysql SUM function to a variable, then display that value within a table with php echo.
PHP
$result = $mysqli->query($sql);
if ($result = mysqli_query($mysqli, $sql)) {
while($row = $result->fetch_array()) {
$code = $row['code'];
$name = $row['name'];
$cost = $row['cost'];
$price = $row['price'];
$vat = $row['vat'];
$stock = $row['onhand']; **Result from the Mysql SUM**
...........}
HTML TABLE
echo "<td>" . $name . " </td>";
echo "<td>" . $cost . " </td>";
echo "<td>" . $price . " </td>";
echo "<td>" . $vat . " </td>";
echo "<td>" . $stock . " </td>";
The Mysql query does work as I've tested it in Mac Terminal Mysql but when I attempt to replicate that in php, the $stock is not getting echoed to the table cell??
Cheers

Answer 1

I'm pretty sure your missing a group by in your sql. Maybe changing it to
SELECT tbl1.code, tbl1.name, tbl1.cost, tbl1.price, tbl1.vat, sum(tbl2.onhand) as onhand
FROM tbl1
INNER JOIN tbl2 ON tbl1.code=tbl2.code
WHERE (tbl2.name='AC' OR tbl2.name='WH') AND tbl1.code IN ($in)
GROUP BY tbl1.code, tbl1.name, tbl1.cost, tbl1.price, tbl1.vat
might work.
Also notice how I changed tble.price to tbl1.price since it looks like a typo

Answer 2

just wanna point out a fact...
hope you are aware that sum is an aggregate function...so using it without a group by clause will cause it to return a just a single row containing the sum total of all the records
SELECT tbl1.code, tbl1.name, tbl1.cost, tbl1.price, tbl1.vat, sum(tbl2.onhand) as onhand
FROM tbl1
INNER JOIN tbl2 ON tbl1.code=tbl2.code
WHERE (tbl2.name='AC' OR tbl2.name='WH') AND tbl1.code IN ($in)
GROUP BY tbl1.code, tbl1.name, tbl1.cost, tbl1.price, tbl1.vat