How to make it shorter and better?

Hello,,,

I don't know much about PHP+SQL but I have to find the better way to make my
query work and to be shorter and better.
All help will be appreciated.

//Check if IP exists in banIP
$res = mysql_query("SELECT ip FROM banIP WHERE ip =
'".$_SERVER['REMOTE_ADDR']."'");
$res = mysql_num_rows($res);
if($res != 0)
 die;
mysql_free_result($res);

//Fetch Time
$timestamp = time();
$timeout = $timestamp - 900;
//Delete Users
$del = mysql_query("DELETE FROM caspionet WHERE timestamp<$timeout");

//Check if IP exists in caspionet
$res = mysql_query("SELECT ip FROM caspionet WHERE ip =
'".$_SERVER['REMOTE_ADDR']."'");
$res = mysql_num_rows($res);
if($res == 0){
 //Insert User
 $ins = mysql_query("INSERT INTO caspionet (timestamp, ip)
VALUES('$timestamp','".$_SERVER['REMOTE_ADDR']."')");
}
mysql_free_result($res);

//Fetch Users Online
$res = mysql_query("SELECT DISTINCT ip FROM caspionet");
while ($row = mysql_fetch_array($res, MYSQL_BOTH)){
 print("IP:$row[0]");
}
mysql_free_result($res);

Thank you
A.K.
Received on Mon May 1 03:07:16 2006