I am stuck with this code, trying to post 2 different radio group my problem is I want to make the user to check 1 radio button for ervery 4 results , I mean how can I know when user has choose other, with this code I always can choose more than one radio , any help?

```
                $sql = "SELECT * FROM tbl1 WHERE object = '".$obj."' LIMIT 5 ";
                $result2 = mysqli_query($conn,$sql);

              echo "<form action='' method='post'>";
                  while ($row2 = mysqli_fetch_array($result2,MYSQLI_ASSOC)) {

                    echo "<div align='center'>
                    <table class='demo'  dir='rtl'>
                      <tbody>
                      <tr>
                        <td>".$row2['ojs']."</td>
                        <td> </td>
                      </tr>
                      <tr>
                        <td>".$row2['txt1']."</td>
                        <td><input type='radio' name='chk1' value='1' >
                      </tr>
                      <tr>
                        <td>".$row2['txt2']."</td>
                        <td><input type='radio' name='chk2' value='2' >
                      </tr>
                      <tr>
                        <td>".$row2['txt3']."</td>
                        <td><input type='radio' name='chk3' value='3' >
                      </tr>
                      <tr>
                        <td>".$row2['txt4']."</td>
                        <td><input type='radio' name='chk4' value='4' >
                      </tr>
                      </tbody>
                    </table><br>
                    </div>
                    ";
                  }
                  echo "<input type='submit' name='submit'>
                  </form>";
                  if (isset($_POST['submit'])) {
                    $chk1 = $_POST['chk1'];
                    $chk2 = $_POST['chk2'];
                    $chk3 = $_POST['chk3'];
                    $chk4 = $_POST['chk4'];
                    echo $chk4."|".$chk3."|".$chk2."|".$chk1;

//insert into mysql , just the Selected radio button for each different question
$insQry = "insert into tbl2 (id,sel1,sel2,sel3,sel4) VALUES('$chk1','$chk2','$chk3','$chk4')";
if (mysqli_query($conn, $sql)) {
echo "New record created successfully";
} else {
    echo "Error: " . $sql . "<br>" . mysqli_error($conn);
}
                  }

```