title: How to compare comma separated values and with two different ids-php mysql
body: <p>The pictures of person shown are just fake data.
  <img src="https://i.stack.imgur.com/XkQ9l.jpg" alt="">This is my table structure</p>
  
  <p>id&nbsp;&nbsp; | Author &nbsp;&nbsp;  | &nbsp;  Co-authors</p>
  
  <p>1&nbsp;&nbsp;&nbsp; |&nbsp;Ronnie &nbsp;  |  &nbsp; vinay, gopal, arun<br/>
  2&nbsp;&nbsp;&nbsp; |&nbsp;Razor&nbsp;&nbsp;&nbsp;&nbsp;    | &nbsp;  karthick, webster, ming<br/>
  3&nbsp;&nbsp;&nbsp; |&nbsp;Taz&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;      | &nbsp;  earl, karthick, vinay<br/>
  4&nbsp;&nbsp;&nbsp; |&nbsp;Baron&nbsp;&nbsp;&nbsp;    | &nbsp;  gopal, arun, sanjeev<br/></p>
  
  <p>Now I want to select two authors say ronnie and baron, so now their co-authors should be compared. In this case the matches would be gopal, arun so the output should gopal and arun.</p>
  
  <p>How to do that in mysql query. Please help.</p>