gan ane butuh bantuan..pake script php kya gni

<?php

include "header.php";

$username=$_SESSION['username'];

$SessionId=$_SESSION['transaksi'];



function InsertToOrder($SessionId)

\t{

$Cart=array();

$QShoppingCart=mysql_query("SELECT * FROM tabelpesan WHERE idtransaksi='$SessionId'");

\t\twhile($r=mysql_fetch_array($QShoppingCart)){

\t\t\t$Cart[]=$r;

\t\t}

\t\t

\t\treturn $Cart;

\t}\t

\t

//CREATE ID ORDER

\t$InsOrder=mysql_query("INSERT INTO nota(username,TanggalOrder,status)

\t\t\t\t\t\t\tVALUES('".$username."','".date('Y-m-d'."','pending'");

\t

\t

\t//MENDAPATKAN ID ORDER YANG TERCIPTA SECARA OTOMATIS KARENA KOLOM IDORDER AUTOINCREAMENT

\t$IDnota=mysql_insert_id();

\t

\t//MEMBUAT SESSION IDORDER

\t$_SESSION['IDnota']=$IDnota;

\t

\t//MENDEKLARASIKAN SEBUAH VARIABLE TERHADAP FUNGSI InsertToOrder()

\t$ShowCart=InsertToOrder($SessionId);

\t\t

\t//INSERT DATA INTO ORDER DETAIL

\tfor($i=0;$i<=count($ShowCart);$i++)

\t{

\t

\t\t$Ins=mysql_query("INSERT INTO DetailOrder (IDnota, idproduk, JumlahBeli)

\t\t\t\t\t\t\t\tVALUE('".$IDnota."','{$ShowCart[$i]['idproduk']}','{$ShowCart[$i]['jumlah']}'");

\t

\t}

\t//DELETE DATA IN SHOPPINGCART

\t$Del=mysql_query("DELETE FROM tabelpesan WHERE idtransaksi='".$SessionId."'");

\t

\techo "Pesanan segera diproses";

?> 

keluar notice kya gini

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