title: return mySQL original row number
body: <p>I want to get the row_number of the original record in the database. Is there any way to retrieve the original row number of a record in mysql?
  Suppose my statement is </p>
  
  <pre><code>select course_id from course where subject='finance';
  </code></pre>
  
  <p>there can be multiple records for this query. Suppose they are from row numbers 4, 5, 7, 9 and 10. How can i retrieve these row_numbers from my query?</p>