title: Version Tracking with mysql
body: <p>I have an database with books.</p>
  
  <p>One book has one Author, Publisher.
  Some Prices, ID's and Descriptions.</p>
  
  <p>I want to keep track of changes made to one product. One way is to save the product with time AND id as primary key.</p>
  
  <p>Are there other ways?</p>
  
  <p>Are there database systems (i've only used mysql) who can keep track of changes automaticly?</p>
  
  <p>greetings...</p>