form

 <form method="GET" class="form-inline align-self" style="margin-left:2%; margin-top:15px;">
           <div class="input-group mb-2 mr-sm-2 mb-sm-0">
             <div class="input-group-addon">Where?</div>
             <select class="custom-select mb-2 mr-sm-2 mb-sm-0 form-control" name="choice">

               <option selected> <?php echo(isset ($_GET["choice"]))?$_GET["choice"]:"Choix..";?></option>
                 <option value="PROJECT">Projet</option>
                 <option value="ACCOUNT">Utilisateur</option>
             </select>
           </div>

           <button type="submit" class="btn btn-primary">Valider</button>

           <?php
            if (isset( $_GET['choice'] )) {
              ?>
              <div class="input-group mb-2 mr-sm-2 mb-sm-0">
                <div class="input-group-addon">Table?</div>
                <select class="custom-select mb-2 mr-sm-2 mb-sm-0 form-control" name="table">
                  <option selected>Choix..</option>
                    <?php
                      $req = getDB()->prepare('SELECT * FROM '.$_GET['choice'].';');
                      $req -> execute();
                      $row = $req->fetch(PDO::FETCH_ASSOC);
                      foreach ($row as $key => $value) {
                        echo '<option>'.$key.'</option>';
                      }
                      $req->closeCursor();
                     ?>
                </select>
              </div>
              <input type="text" class="form-control mb-2 mr-sm-2 mb-sm-0" name="search" placeholder="mot clef de recherche">
              <button type="submit" class="btn btn-primary">Rechercher</button>
              <?php
              if (isset( $_GET['table'] )) {
                ?>
                <div class="zone container" style="margin-left:2%;margin-bottom:2%;width: 96%;overflow: scroll;height: 500px">
                <table class="table table-bordered table-hover">
                   <thead>
                     <tr>
                       <?php
                       $req = getDB()->prepare('SELECT * FROM '.$_GET['choice'].' WHERE '.$_GET['table'].' = '.$_GET['search'].';');
                       $req -> execute();
                       $row = $req->fetch(PDO::FETCH_ASSOC);
                       foreach ($row as $key => $value) {
                         echo '<th>'.$key.'</th>';
                       }
                       echo "</tr>
                     </thead>
                     <tbody>";
                       $req -> execute();
                       while ($row = $req->fetch(PDO::FETCH_ASSOC)) {
                         echo '<tr>';
                           foreach ($row as $key => $value) {
                             echo '<td>'.$value.'</td>';
                           }
                         echo '</tr>';
                       }
                       $req->closeCursor();
                      ?>

                   </tbody>
                 </table>
                <?php
              }
              else {
                echo'
                <div class="zone container" style="margin-left:2%;margin-bottom:2%;width: 96%;overflow: scroll;height: 500px">
                  <h5 style="text-align:center"> Il manque des paramètres </h5>
                ';
              }
            }
            else {
              echo'
              <div class="zone container" style="margin-left:2%;margin-bottom:2%;width: 96%;overflow: scroll;height: 500px">
              ';
            }
            ?>


         </div>
       </form>