Lancer une requete depuis liste deroulante

Bonjour,

<h1>Comment lancer des requetes à partir d'une liste déroulante?</h1>

<form action="programmeTV.php" name="chaines" method="get">
<select name="chaine">

<option value="voirtout" onclick='this.form.submit();'>Toutes les chaines</option>

<option value="TF1" onclick='this.form.submit();'>TF1</option>

<option value="france2" onclick='this.form.submit();'>france2</option>

<option value="france3" onclick='this.form.submit();'>france3</option>

</form>


<?php
switch ($_GET['chaine'])
{
case voirtout:
include("bddconnect.php");
$resultat=mysql_query("SELECT * FROM table WHERE chaine='TF1' OR chaine='france2' OR chaine='france3'");
break;

case TF1:
$resultat = mysql_query("SELECT * FROM table WHERE chaine='TF1'");
break;

case france2:
$resultat = mysql_query("SELECT * FROM table WHERE chaine='france2'");
break;

case france3:
$resultat = mysql_query("SELECT * FROM table WHERE chaine='france3'");
break;
}
?>


<h1>Programme TV</h1>


<table width="390" align="center" border="0" style="border:solid 1px lightblue;" cellspacing="0" cellpadding="0">
<tr>
<th class="espace" style="background:lightblue">Heure</th>
<th class="espace" style="background:lightblue">Film</th>
<th class="espace" style="background:lightblue">Chaine</th>
</tr>
<?php while ($donnees= mysql_fetch_assoc($resultat)) { ?>

<tr>

<td align="center" class="espace6"><?php echo $donnees['heure'];?></td>
<td align="center" class="espace6"><?php echo $donnees['film'];?></td>
<td align="center" class="espace6"><?php echo $donnees['chaine'];?></td>
</tr>
<?php } ?>
</table>