title: How to perform a range query over AWS dynamoDB
body: <p>I have a AWS DynamoDB table storing books information, the hash key is book id. There is an attribute for book price.</p>
  
  <p>Now I want to perform a query to return all the books whose price is lower than a certain value. How to do this efficiently, without scanning the whole table? </p>
  
  <p>The query on secondary-index seems only could return a set of entries with the index being a certain value, so I am confused about how to perform a range query efficiently. Thank you very much!</p>