Php/mysql formulaire + base de données

<?php
if(isset($_POST['Code_barre']) && isset($_POST['Designation']) && isset($_POST['Rayon']) && isset($_POST['Famille']) && isset($_POST['Poids']) && isset($_POST['Point_de_fidelite']) && isset($_POST['Date_de_sortie']) && isset($_POST['Prix_de_reprise'])&& isset($_POST['Tva']) && isset($_POST['Vente_TTC'])&& isset($_POST['Vente_HT'])&& isset($_POST['Stock'])&& isset($_POST['Neuf'])&& isset($_POST['Occasions']) && $_POST['Code_barre'] != "" && $_POST['Designation'] != "" && $_POST['Rayon'] != "" && $_POST['Famille'] != "" && $_POST['Poids'] != "" && $_POST['Point_de_fidelite'] != "" && $_POST['Date_de_sortie'] != "" && $_POST['Prix_de_reprise'] != "" && $_POST['Tva'] != "")&& $_POST['Vente_TTC'] != "")&& $_POST['Vente_HT'] != "")&& $_POST['Stock'] != "")&& $_POST['Neuf'] != "")&& $_POST['Occasions'] != ""){
    $Code_barre = $_POST['Code_barre']; 
    $Designation =$_POST['Designation']; 
	$Rayon = $_POST['Rayon']; 
	$Famille =$_POST['Famille']; 
	$Poids = $_POST['Poids']; 
	$Point_de_fidelite = $_POST['Point_de_fidelite']; 
	$Date_de_sortie = $_POST['Date_de_sortie']; 
    $Prix_de_reprise = $_POST['Prix_de_reprise']; 
	$Stock = $_POST['Stock']; 
	$Neuf = $_POST['Neuf']; 
	$Occasions= $_POST['Occasions']; 
 $connect= mysql_connect('localhost','articles','31p71h49') or die('Impossible de se connecter au serveur MySQL');
    mysql_select_db("articles");  
    mysql_query("INSERT INTO articles (Code_barre,Designation,Rayon,Famille,Poids,Point_de_fidelite,Date_de_sortie,Prix_de_reprise,Stock,Neuf,Occasions)VALUES('$Code_barre','$Designation','$Rayon','$Famille','$Poids','$Point_de_fidelite','$Date_de_sortie','$Prix_de_reprise','$Tva','$Vente_TTC','$Vente_HT','$Stock','$Neuf','Occasions')");
	}
?>
<form method="POST" action="nouveauxarticle.php">
<p><font color="red">/!\ Tous les champs doivent être remplis /!\</font></p>
<p>Code barre</p>
<input type="text" name="Code_barre"/>
<p>Designation</p>
<input type="text" name="Designation"/>
<p>Rayon</p>
<input type="text" name="Rayone"/>
<p>Famille</p>
<input type="text" name="Famille"/>
<p>Poids</p>
<input type="text" name="Poids"/>
<p>Point de fidelite</p>
<input type="text" name="Point_de_fidelite"/>
<p>Date de sortie</p>
<input type="text" name="Date_de_sortie"/>
<p>Prix de reprise</p>
<input type="text" name="Prix_de_reprise"/>
<form><SELECT name="Tva" size="1">
<OPTION>0
<OPTION>2.1
<OPTION>5.5
<option>7
<option>19.6
<p>Vente TTC</p>
</form>
<input type="text" name="Vente_TTC"/>
<p>Vente HT</p>
<input type="text" name="Vente_HT"/>
<p>Stock</p>
<input type="text" name="Stock"/>
<FORM>
<INPUT type="checkbox" name="Neuf" value="1"> Neuf
<INPUT type="checkbox" name="Occasions" value="2"> Occasions
</FORM>
<input type="submit" name="Validez" value="Valider"/>
</form>