Drop down list box

Techissue2008

I created a drop down list box but it cannot show the result. Here is my code:

<form>
<?php
$query4 = "select sname from student"; 
$result4 = mysql_query($query4) or die('Error : ' . mysql_error());
echo '<select name="student" onchange="this.form.submit()">'; 
while($row=mysql_fetch_array($result4)){  

echo '<option value="' . $row['sname'] . '">' . $row['sname'] . '</option>'; 
} 
echo '</select>';  

?>
</form>

After that, I want to select the student name and show his score by the follow SQL:

Select score from student where sname = '$sname'; //here is the problem!!

There is no id primary key for that table, only has 2 columns: sname and score.

Thanks for help

laserlight

The drop down menu is named "student", so you should access $POST['student'] or $GET['student'], as the case may be.

There is no id primary key for that table, only has 2 columns: sname and score.

Make sname the primary key then.

Techissue2008

I added if(isset($_GET['student'])), but still show nothing

laserlight

You would write:

if (isset($_GET['student']))
{
    $query = sprintf("Select score from student where sname = '%s'",
                     mysql_real_escape_string($_GET['student']));
    $result = mysql_query($query);
    if (mysql_num_rows($result) == 1)
    {
        $score = mysql_result($result, 0);
        echo htmlspecialchars($_GET['student']) . ' scored ' . (int)$score;
    }
}