Mysqli_query

<form method="post" action="login.php">
                              <div align="center"><b><font face="Verdana, Arial, Helvetica, sans-serif" size="1"> </font></b>
                                  <table width="280"  border="0">
                                    <tr>
                                      <td><b><font face="Verdana, Arial, Helvetica, sans-serif" size="2">Login</font></b></td>
                                      <td><b><font face="Verdana, Arial, Helvetica, sans-serif" size="1">
                                        <input type="text" name="pseudo">
                                      </font></b></td>
                                    </tr>
                                    <tr>
                                      <td><b><font face="Verdana, Arial, Helvetica, sans-serif" size="2">Mot de passe</font></b></td>
                                      <td><input type="password" name="passe"></td>
                                    </tr>
                                    <tr>
                                      <td> </td>
                                      <td><div align="center">
                                          <input type="submit" name="Submit" value="Entrer" class="input">
                                      </div></td>
                                    </tr>
                                  </table>
                              </div>
                            </form>

<?php 
require("protec/passe/conf.php");

$db_link = mysqli_connect($sql_serveur,$sql_user,$sql_passwd,$sql_bdd);
$requete=mysqli_query($db_link,"select * from $table where pseudo=\"$pseudo\" and passe=\"$passe\"");
if(mysqli_num_rows($requete)==0)
 {
 header("Location:$url_erreur");
 exit;
 }
else
$destination=mysqli_result($requete,$i,"destination");
 {
 $taille = 20;
 $lettres = "abcdefghijklmnopqrstuvwxyz0123456789";
 srand(time());
 for ($i=0;$i<$taille;$i++)
  {
  $id.=substr($lettres,(rand()%(strlen($lettres))),1);
  }
  
 $requete=mysqli_query($db_link,"update $table set id=\"$id\" where pseudo=\"$pseudo\" and passe=\"$passe\"");
 
 header("Location:$destination?id=$id");
 } 

mysqli_close($db_link);
?>