MySQL-对已登录用户的重复行求和

Question

I'm trying to do some simple math in mySQL. I've got a User table and an Activities table. Each activity is worth so many points. I can get the activities to show properly based on matching the User to a $_SESSION variable Dreamweaver set up when I did the "User Authentication > Log in User". I can even get it to display the SUM of the column.

What I CAN'T get it to do is display the Total points of said column using ONLY that users activities. I'm a mySQL rookie using Dreamweaver to do the heavy lifting and I've tried every combination of WHERE statements and SUM() combos I can think of.

Here's my select statement:

$MM_Username_physTotal = "username";
if (isset($_SESSION['MM_Username'])) {
  $MM_Username_physTotal = $_SESSION['MM_Username'];
}
mysql_select_db($database_som13connect, $som13connect);
$query_physTotal = sprintf("SELECT SUM(activity.Phys_points) FROM activity WHERE activity.`User` = %s", GetSQLValueString($MM_Username_physTotal, "text"));
$physTotal = mysql_query($query_physTotal, $som13connect) or die(mysql_error());
$row_physTotal = mysql_fetch_assoc($physTotal);
$totalRows_physTotal = mysql_num_rows($physTotal);

And here's the CURRENT statement Dreamweaver inserts when I select the above binding:

<?php echo $physTotal['Phys_points']; ?>

Any help would be appreciated!

Answer 1

Try adding quotes around %s

$query_physTotal = sprintf("SELECT SUM(activity.Phys_points) FROM activity WHERE activity.`User` = '%s'", GetSQLValueString($MM_Username_physTotal, "text"));

You need to surround varchar/text values with single quotes within your SQL query