gtw

<!DOCTYPE html>
<html>
<head>
	<title>Percobaan Ajax</title>
	<link rel="stylesheet" type="text/css" href="assets/css/bootstrap.min.css">
	<script type="text/javascript" src="assets/js/jquery.min.js"></script>
<script type="text/javascript" src="assets/js/bootstrap.min.js"></script>

</head>
<body>
    <form method="post">
<h3 class="text-center">PPDB ESDEH !1!1</h3>
<div class="col-lg-6 col-lg-offset-3">
	<input type="text" name="nama" id="nama" class="form-control"><br>
	<input type="text" name="alamat" id="alamat" class="form-control"><br>
	<input type="text" name="wali" id="wali" class="form-control"><br>
	<input type="text" name="asal" id="asal" class="form-control"><br>
	<button id="tombol" class="btn btn-primary">Add</button>
</div>
</form>
<?php

$connect = mysqli_connect("localhost", "root", "", "ajax");

    if (isset($_POST['tombol'])) {
        $nama = $connect->real_escape_string($_POST['nama']);
    $alamat = $connect->real_escape_string($_POST['alamat']);
    $wali = $connect->real_escape_string($_POST['wali']);
    $asal = $connect->real_escape_string($_POST['asal']);
    $sql = $connect->query("SELECT * FROM siswa WHERE nama = '$nama'");
    if ($sql->num_rows > 0) {
      echo "Already";
    }
    else{
        $connect->query("INSERT siswa
                VALUES('','$nama','$alamat','$wali','$asal')");
            echo"Siswa Berhasil Ter Daftarkan";
    }
    }

?>
</body>
</html>