<?php
define('HOST','localhost');
define('USER','usernamedatabase');
define('PASS','pasword');
define('DB','namadatabase');

$con=mysqli_connect(HOST,USER,PASS,DB)or die('gagal terhubung ke server');
$username=$_GET['username'];
$password=$_GET['password'];
$email=$_GET['email'];

if($username == '' || $password == '' ||$email == ''){
echo'Mohon isikan semua data';

}else{
$sql="SELECT * from user where username='$username' OR email='$email'";
$check=mysqli_fetch_array(mysqli_query($con,$sql));
if(isset($check)){
echo 'Username atau Password sudah ada';
}else{
$sql="INSERT INTO user(username,password,email) values('$username','$password','$email')";

if(mysqli_query($con,$sql)){
echo'Registrasi berhasil';

}else{
echo'Registrasi gagal,Silakan coba lagi';
}
}
mysqli_close($con);
}