title: Spark: How to convert RDD[(Long, Iterable[String])] to RDD[(Long, String)]?
body: <p>How to convert this RDD[(Long, Iterable[String])] to...</p>
  
  <pre><code>(852403,Set(PT0000094043, PT0000097083, PT0000036162))
  (357331,Set(PT0000068829, PT0000094042, PT0000066859))
  </code></pre>
  
  <p>RDD[(Long, String)] like this ?</p>
  
  <pre><code>(852403, PT0000094043)
  (852403, PT0000097083)
  (852403, PT0000036162)
  (357331, PT0000068829)
  (357331, PT0000094042)
  (357331, PT0000066859)
  </code></pre>