title: Database design question on E-Commerce application
body: <p>I´m designing an ecommerce database...
  I´d like suggestion to design the following case :</p>
  
  <ul>
  <li>A product may have several sizes and several colors</li>
  <li>Each combination of products´s size/color must have a specific price</li>
  </ul>
  
  <p>So, I can have a Product X with sizes:
  A,B,C
  and colors:
  Green,Black and White</p>
  
  <p>And each combination have its price... </p>
  
  <p>It´s implemented in Amazon, one example here :
  <a href="https://rads.stackoverflow.com/amzn/click/com/B0010EEYCU" rel="nofollow noreferrer" rel="nofollow noreferrer">http://www.amazon.com/Champion-Mens-Jersey-Black-Large/dp/B0010EEYCU/ref=sr_1_4?ie=UTF8&amp;s=sporting-goods&amp;qid=1287767784&amp;sr=1-4</a></p>
  
  <p>I´d like help in designing that !</p>
  
  <p><strong>EDIT: A Product can have a price without Size nor Color</strong></p>
  
  <p>Thanks</p>