Bouton submit et onclick

<form method=POST action="http://10.212.80.71/cdp/passage.php"> 
	<table width='690px'>
		<tr>
			<th>Nom de la station : </th>
			<td> 
				<select id='type' name= 'station'>
				<option VALUE="" ></option>
				<?php 
				$result=mysql_query("select distinct nom from STATION where secteur = 'Toulouse Sud'") or die (mysql_error());	
				echo "<option VALUE='Toulouse Sud' >+++ TOULOUSE SUD +++</option>";
				while ($ligne= mysql_fetch_array($result))
				{
				       echo "<option VALUE='$ligne[0]' >$ligne[0] </option>";
								 
				}
				$result=mysql_query("select distinct nom from STATION where secteur = 'Toulouse Nord'") or die (mysql_error());	
				echo "<option VALUE='Toulouse Nord' >+++ TOULOUSE NORD +++</option>";
				while ($ligne= mysql_fetch_array($result))
				{
					 echo "<option VALUE='$ligne[0]' >$ligne[0] </option>";
				}
				$result=mysql_query("select distinct nom from STATION where secteur = 'Toulouse Est'") or die (mysql_error());	
				echo "<option VALUE='Toulouse Est' >+++ TOULOUSE EST +++</option>";
				while ($ligne= mysql_fetch_array($result))
				{
					echo "<option VALUE='$ligne[0]' >$ligne[0] </option>";
				}
				?>
				</select>
				</td>

				</tr>
				<tr><td><br/></td></tr>
				<tr>
					<th>Noms des Personnes :</th>
					<td>
						<?php 
							$result=mysql_query("select nom1,nom2 from EQUIPE where id_equipe = '3';" ) or die (mysql_error());	
							while ($ligne= mysql_fetch_array($result))
							{
								$nom1est= split (" ",$ligne[0]);
								$nom2est= split (" ",$ligne[1]);
								
								echo "<input name=equipe type='radio' value = '3'>$nom1est[1] / $nom2est[1]";
							}
						?>
					</td>
					<td>
						<?php 
							$result=mysql_query("select nom1,nom2 from EQUIPE where id_equipe = '2';" ) or die (mysql_error());	
							while ($ligne= mysql_fetch_array($result))
							{
								$nom1nord= split (" ",$ligne[0]);
								$nom2nord= split (" ",$ligne[1]);
								
								echo "<input name=equipe type='radio' value ='2'>$nom1nord[1] / $nom2nord[1]";
							}
						?>
					</td>
					<td>
						<?php 
							$result=mysql_query("select nom1,nom2 from EQUIPE where id_equipe = '1';" ) or die (mysql_error());	
							while ($ligne= mysql_fetch_array($result))
							{
								$nom1sud= split (" ",$ligne[0]);
								$nom2sud= split (" ",$ligne[1]);
								
								echo "<input name=equipe type='radio' value = '1'>$nom1sud[1] / $nom2sud[1]";
							}
						?>
					</td>				
				</tr>
				<tr><td><br/></td></tr>
				<tr>
					<th> Ou : </th>
					<td>
						<select id='type' name= 'nom1'>
							<option VALUE="" ></option>
						<?php 
							$result=mysql_query("select nom from Nom where Nom.nom not like '%Toulouse%' ");	
							while ($ligne= mysql_fetch_array($result))
							{
								echo "<option VALUE='$ligne[0]' >$ligne[0]</option>";
							}
						?>
						</select>
					</td>
					<td>
						<select id='type' name= 'nom2'>
							<option VALUE="" ></option>
						<?php 
							$result=mysql_query("select nom from Nom where Nom.nom not like '%Toulouse%'");	
							while ($ligne= mysql_fetch_array($result))
							{
								echo "<option VALUE='$ligne[0]' >$ligne[0]</option>";
							}
						?>
						</select>
					</td>
				</tr>
				<tr><td><br/></td></tr>
				<tr>
					<th> Veuillez entrez une date : </th>
					<td>
						<input onclick="ds_sh(this);" name="date" readonly="readonly" style="cursor: text" /><br />
					</td>
				</tr>
				<tr><td><br/></td></tr>
			</table>
			<input type= "button" value="Nouveau Dossier" ></p>
			
		</form>	

<?php 

			If ($_POST['station']!= NULL)
			{
				If (($_POST['date']) != NULL)
				{
					$date = mysql_real_escape_string(htmlspecialchars($_POST['date']));
				}

				If ($_POST['equipe'] !=NULL)
				{
					$idEquipeSelection = mysql_real_escape_string(htmlspecialchars($_POST['equipe'])); 
					$station = mysql_real_escape_string(htmlspecialchars($_POST['station']));
					$result=mysql_query("select id_station from STATION where Nom = '$station'");	
					while ($ligne= mysql_fetch_array($result))
					{
						$id_station = $ligne[0];
					}
				
				}
				 
				
				If (($_POST['nom1']!= NULL) and ($_POST['nom2']!=NULL))
				{
					$station = mysql_real_escape_string(htmlspecialchars($_POST['station']));
					$result=mysql_query("select id_station from STATION where Nom = '$station'");	
					while ($ligne= mysql_fetch_array($result))
					{
						$id_station = $ligne[0];
					}
					$nom1 = mysql_real_escape_string(htmlspecialchars($_POST['nom1']));
					$nom2 = mysql_real_escape_string(htmlspecialchars($_POST['nom2']));
				// On peut enfin enregistrer 
				mysql_query("INSERT INTO EQUIPE (nom1,nom2) VALUES('$nom1','$nom2')") or die (mysql_error());
				$result = mysql_query("SELECT id_equipe FROM EQUIPE ORDER BY id_equipe DESC LIMIT 0,1");
				$row = mysql_fetch_array($result) or die (mysql_error());
				$dernierID = $row["id_equipe"];
				}
				mysql_query("INSERT INTO DOSSIER (id_station,id_equipe,date) VALUES('$id_station','$dernierID','$date')") ;
			}else{
				echo "<b> Veuillez remplir tous les champs svp.</b>";}