how to total all row in page that was sql LIMIT - php

Question

i put limit in this code but how can i calculate the totalmin in this page?
here is my code
<?php
$id = $_GET['id'];
$sql = "SELECT * FROM time WHERE id = $id ORDER BY id DESC LIMIT 15";
$result = mysql_query($sql);
?>
<table border="0" style="width:50%">
<tr>
<th>Time in</th>
<th>Time Out</th>
</tr>
<?php
while($row = mysql_fetch_array($result)){
echo "<tr>";
echo "<td><center>".$row['totalmin']."</center></td>";
echo "</tr>";
}
</table>
mysql_close();
i want to know how to total all the mins in 15 row with php code

Answer 1

Something like this may do the trick, if you want to show sum only
But you should NOT use mysql_ functions, and this code is not sequre from SQL Injects
$id = $_GET['id'];
$sql = "SELECT * FROM time WHERE id = $id ORDER BY id DESC LIMIT 15";
$result = mysql_query($sql);
$sum = 0;
$num = 0;
?>
<table border="0" style="width:50%">
<tr>
<th>Time in</th>
<th>Time Out</th>
</tr>
<?php
while($row = mysql_fetch_array($result)){
$num++;
$sum += $row['totalmin'];
echo "<tr>";
echo "<td><center>".$row['totalmin']."</center></td>";
echo "</tr>";
if($num == 15){
echo "<tr>";
echo "<td><center>".$sum."</center></td>";
echo "</tr>";
}
}
?>
</table>
<?php
mysql_close();

Answer 2

You need to store $totalmin into your while loop and update it with new value if $row['totalmin'] is less then $totalmin.
Use something like this:
$totalmin = null;
while($row = mysql_fetch_array($result)) {
if (is_null($totalmin) || $row['totalmin'] < $totalmin) {
$totalmin = $row['totalmin'];
}
echo "<tr>";
echo "<td><center>" . $totalmin . "</center></td>";
echo "</tr>";
}

Answer 3

Sum up the minutes as you loop through the result:
$sum = 0;
while($row = mysql_fetch_array($result)){
$sum += floatval($row['totalmin']); //or intval()
echo "<tr>";
echo "<td><center>".$row['totalmin']."</center></td>";
echo "</tr>";
}
echo $sum;
make sure you close your while loop