title: designing database to hold different metadata information
body: <p>So I am trying to design a database that will allow me to connect one product with multiple categories. This part I have figured. But what I am not able to resolve is the issue of holding different type of product details. </p>
  
  <p>For example, the product could be a book (in which case i would need metadata that refers to that book like isbn, author etc) or it could be a business listing (which has different metadata) .. </p>
  
  <p>How should I tackle that?</p>