galau liat kondisi if

<?php
        defined( 'SYSDIR' ) or exit();
        $status = mysql_query("SELECT * FROM belanja ORDER BY kode DESC LIMIT 1");
        $buku = mysql_fetch_array( $status );

if( isset( $_POST['beli'] ) )
{
                $nama_barang = $_POST['nama_barang'];
                $harga_satuan = $_POST['harga'];
                $jumlah = $_POST['jumlah'];
                $total = $_POST['total'];
                $status = 'Keluar';

                $cekKode = mysql_num_rows( mysql_query( "SELECT * FROM belanja WHERE kode='$kode'" ) );
                $getData = mysql_fetch_array( mysql_query( "SELECT * FROM belanja WHERE kode='$kode'" ) );

} //if( isset( $_POST['beli'] ) )

//==================ngak ada POST yg terjadi tapi melakukan insert... ada yang ganjil???

 $beli = mysql_query("INSERT INTO belanja (nama_barang,harga,jumlah,total,status) VALUES ('".@$_POST['nama_barang']."','".@$_POST['harga']."','".@$_POST['jumlah']."','".@$_POST['total']."','".@$_POST['status']."')") or die(mysql_error());
                        echo '<strong>Sukses:</strong> Data telah berhasil disimpan';

?>
<style>
        input.qty, input.jumlah {
                margin:0; padding:0; border:0; outline:none; background:transparent; color:#000;
        }
        input.qty:focus {
                 background:#303030; color:#fff;
        }
        span.nama {
                padding:0 10px;
        }
        span.harga {
                padding:0 10px;
        }
        td.hapus {
                cursor:pointer;
        }
        td.hapus:hover {
                background:-webkit-linear-gradient(top,#fff,#fafafa);
        }
        td.hapus:active {
                background:-webkit-linear-gradient(top,#c0c0c0,#d0d0d0);
        }
</style>

<form id="tambah_data_pengeluaran" action="" method="post" enctype="multipart/form-data">
<fieldset>
        <legend>Pengeluaran</legend>
        <p>
                <div style="background:#f0f0f0; display:block; padding:4px 10px; margin:4px 0px; border-bottom:1px solid #c0c0c0">
                        <table>
                                <tr>
                                        <td>Nama Barang</td>
                                        <td>:</td>
                                        <td><input type="text" name="nama_barang" class="nama_barang" /></td>
                                </tr>
                                <tr>
                                        <td>Harga Satuan</td>
                                        <td>:</td>
                                        <td><input type="text" name="harga_satuan" class="harga_satuan number" /></td>
                                </tr>
                                <tr>
                                        <td>Jumlah</td>
                                        <td>:</td>
                                        <td><input type="text" name="jumlah" class="jumlah" /></td>
                                </tr>
                                <tr>
                                        <td>Total</td>
                                        <td>:</td>
                                        <td><input type="text" name="total" class="total number" /></td>
                                </tr>
                                <tr>
                                        <td>Status</td>
                                        <td>:</td>
                                        <td><input type="text" name="status" class="status" /></td>
                                </tr>
                                <tr><td align='right' colspan='3'>
                                <td><input type="submit" class="beli" value="Beli" /></td>
                                <td><input type="button" class="batal" value="Batal" /></td>
                        </tr>
                        </table>
                </div>
        </p>
</fieldset>
</form>
<?php

?>