<?php

$Host = Insert Host Name [DB]
$User = Insert User Name [DB]
$Pass = Insert Pass Name [DB]

mysql_connect("$Host", "$User", "$Pass") or die(mysql_error());
mysql_select_db("Logon");

$User = $_POST['Username'];
$Pass = $_POST['Password'];
$Referal = $_POST['Referal'];

$query = mysql_query(SELECT `recruitedfriend` FROM `accounts` WHERE `recruitedfriend` = $referal);
if($query == NULL ){
  echo "The referal already has one friend registered under his name!";
} else {
  mysql_query(INSERT INTO `accounts` WHERE `recruitedfriend` VALUES $Referal);
}

$uquery = mysql_query(SELECT `Login` FROM `accounts` WHERE `login` = $User);
tr_replace("--", "", mysql_real_escape_string($_POST['username']));
if($uquery == NULL){
   echo "Username already exists!";
} else {
   mysql_query(INSERT INTO `accounts` WHERE `username, password` VALUES $User, $Pass);
}
?>