title: Write a query to display the names of all students who have secured more than 50 in all subjects that they have appeared in?
body: <p>I have been learning sql in online. I have some doubts in this question.
  Tis is my answer but it didnt work properly. </p>
  
  <p><strong>Answer:</strong></p>
  
  <pre><code>select distinct student_name 
    from student s 
    join mark m on s.student_id=m.student_id
   where value &gt; 50 order by student_name;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/3JEAb.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3JEAb.jpg" alt="enter image description here"></a></p>