title: DynamoDBMappingException: no mapping for HASH key
body: <p>When writing a DynamoDB Java App you can receive the 'no mapping for HASH key' error when writing or retrieving from a table if the table and its data model are not configured correctly. The full exception would be similar to:</p>
  
  <p><code>com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: &lt;YourClassNameHere&gt;; no mapping for HASH key</code></p>