title: Streaming pipelines with BigQuery sinks in python
body: <p>I'm building an apache beam streaming pipeline whose source is Pubsub and sink is BigQuery. I've gotten the error messsage:</p>
  
  <p>"Workflow failed. Causes: Unknown message code."</p>
  
  <p>As cryptic as this message is I now believe it to be the case that BigQuery is not supported as a sink for streaming pipelines, it says this here:
  <a href="https://stackoverflow.com/questions/46084361/streaming-from-pub-sub-to-bigquery">Streaming from Pub/Sub to BigQuery</a></p>
  
  <p>Am I certainly correct that this is what's causing the problem? Or if not is it still not supported in any case?</p>
  
  <p>Can anyone hint at when this feature will be released? It's a shame, I was pretty excited to get using this.</p>