php - passing variables in query string

Question

$courses_taken=$row['course_id'];
<a href="course.php?course_id=$courses_taken"></a>

As you can see from above code, i'm taking a variable and passing it in query string, but this method is wrong.

How can i pass a variable in query string, as each user will have opted for different courses, thus they will have different course_id.

Is there a way to do it?

Answer 1

<?php 
    $courses_taken=$row['course_id'];
?>
<a href="course.php?course_id=<?php echo $courses_taken; ?>"></a>