title: Storing a non-unique array in DynamoDB
body: <p>I'm brand new to DynamoDB and finding it surprising how "model driven" a schema-less database can be. Anyway, petty snarkiness out of the way, I am wondering how to declare a property in an item which will be an array of values but one which CAN have duplicate values. </p>
  
  <p>Specifically what I'm storing is wordcloud array of emotive words and if a particular word is used more than once then I want to know that. My simple answer was to have an attribute/property called <strong>wordsPositive</strong> which would be set as type "SS" but it appears this will not allow for duplicate array elements. </p>
  
  <p>The error I get when trying is:</p>
  
  <blockquote>
    <p>400: Input collection [better, excellent, best, important, good, success, best, creative, powerful, benefits] contains duplicates.]</p>
  </blockquote>
  
  <p>Looking at the AWS web interface at a record which did not have duplicates I can see that the structure defined <em>could</em> support duplicated values but given that its calling the list a "set" my guess is that this just isn't allowed: </p>
  
  <p><img src="https://i.stack.imgur.com/TpTx3.png" alt="aws web interface"></p>
  
  <p>What is the best way of doing this in DynamoDB? </p>