Updating info in database

I have tried to make it update the info if it already exists but with no luck, I am a newbie to php and I hope you guys will help me :)
<?php
define("DB_SERVER", "xxxx");

define("DB_USER", "xxxx");

define("DB_PASS", "xxxx");

define("DB_NAME", "xxxx");

mysql_connect(DB_SERVER, DB_USER, DB_PASS);
mysql_select_db(DB_NAME);
session_start();

$runtime = $_GET['runtime'];
$user = $_GET['username'];
$profit = $_GET['profit'];
$exp = $_GET['exp'];

$query = "SELECT * FROM rune_sig WHERE username = '$username'";
$result = mysql_query($query);

if (mysql_num_rows($result) )
{
@mysql_query("UPDATE rune_sig SET runtime = '$runtime', exp = '$exp', profit = '$profit'");
}
else
{
if ($run>=0 && $user && $profit>=0 && $exp>=0) {
@mysql_query("INSERT INTO rune_sig
(`username`, `runtime`, `profit`, `exp`, `time`) VALUES
('$user', '$runtime', '$profit', '$exp', NOW())");
} else {
echo '<font style="font-size:100px;font-family:georgia;"><br><center>GTFO</center></font>';
echo '<font style="font-size:50px;font-family:georgia;"><center><i>These are my PHP files.</i></center></font>';
}
}
?>

Hi

You need to tell MYSQL what row it needs to update. SO adding WHERE username = '$username' onto the end of the update query should do it.

Hi

You need to tell MYSQL what row it needs to update. SO adding WHERE username = '$username' onto the end of the update query should do it.

Hmm, I didn't know that it would clear out the data and set it to the new one. Is there any way to add the value to the current one?

So assuming that its a integer you can do something like this:

profit = profit + '$profit'

but depending on your need you may want to use CSV's so the info would look like this 10,20,30 or a seperate table altogether.

If you explain what you are trying to do in more detail I could suggest some more detailed solutions.

So assuming that its a integer you can do something like this:

profit = profit + '$profit'

but depending on your need you may want to use CSV's so the info would look like this 10,20,30 or a seperate table altogether.

If you explain what you are trying to do in more detail I could suggest some more detailed solutions.

I got it to work, you can't imagine how happy I am right now. Thank you!

No problem buddy