Hello,

I will try to explain this as clearly as I can.

Here is how Database is Designed


Can anyone write a script like this

If 124.195.209.112 already exists, page need to be redirected to loggedin.php else redirect to login.php

Probably not the best way to do this as I am not well experienced with PHP but ill try to help, i will assume you know how to connect to the database...

PHP Code:

$ip = "124.195.209.112";
$q = "SELECT * FROM tablename WHERE ip_address='$ip'";

if (mysql_numrows(mysql_query($q)) > 0) {
header("Location: loggedin.php");
}
else {
header("Location: login.php");
} 


This however is not a great way of checking if someone is logged in or not. For a complete login system with an explanation of what most of the code does go to:
http://www.evolt.org/node/60384