title: sql query to fetch top 3 salaries
body: <pre><code>  emp_name |salary
    ---------------
    A        |12568
    B        |3000
    C        |7852
    D        |2568
    E        |9852
    F        |1598
    G        |8569
  </code></pre>
  
  <p>I want a sql query to fetch the lowest 3 salaried employees</p>