title: Athena query fails with boto3 (S3 location invalid)
body: <p>I'm trying to execute a query in Athena, but it fails.</p>
  
  <p>Code:</p>
  
  <pre><code>client.start_query_execution(QueryString="CREATE DATABASE IF NOT EXISTS db;",
                             QueryExecutionContext={'Database': 'db'},
                             ResultConfiguration={
                                       'OutputLocation': "s3://my-bucket/",
                                       'EncryptionConfiguration': {
                                               'EncryptionOption': 'SSE-S3'
                                               }
                                       })
  </code></pre>
  
  <p>But it raises the following exception:</p>
  
  <pre><code>botocore.errorfactory.InvalidRequestException: An error occurred (InvalidRequestException) 
  when calling the StartQueryExecution operation: The S3 location provided to save your 
  query results is invalid. Please check your S3 location is correct and is in the same 
  region and try again. If you continue to see the issue, contact customer support 
  for further assistance.
  </code></pre>
  
  <p>However, if I go to the Athena Console, go to Settings and enter the same S3 location (for example):</p>
  
  <p><a href="https://i.stack.imgur.com/lij8R.png" rel="noreferrer"><img src="https://i.stack.imgur.com/lij8R.png" alt="athena settings"></a></p>
  
  <p>the query runs fine.</p>
  
  <p>What's wrong with my code? I've used the API of several the other services (eg, S3) successfully, but in this one I believe I'm passing some incorrect parameters.  Thanks.</p>
  
  <p>Python: 3.6.1.  Boto3: 1.4.4</p>