PHP odkaz na vlakno ve foru

<?php
if(isset( $_SESSION["id"])){
    echo "<a href='?str=diskuzepridat'>Přidat</a><br><br>";}




$sql = 'Select * from diskuze';

$sq = mysqli_query($spojeni,$sql);


while($row = mysqli_fetch_array($sq)){
    
   $id = $row["id"];
    
   
echo "<tr><td><a href='vysledek.php?id=" . $id ."'>" . $row["nadpis"] .
        "</a></td><td> " . $row["text"] ."</td><td> <br>";
}
echo "</table>";
//else {echo "neco";}

?>

<?php
if(isset($_GET["id"])){
$id=$_GET["id"];
    
    
   $sql = mysqli_query($spojeni,"SELECT * FROM diskuze WHERE id ='".$id."'");
    $r1 = mysqli_fetch_array($sql);
}
else {echo"neco";}

?>