How to print plan of Structured Streaming DataFrame

[Chang Chen]

Hi Guys

I modified StructuredNetworkWordCount to see what the executed plan is,
here are my codes:

val wordCounts = words.groupBy("value").count()

// Start running the query that prints the running counts to the console
val query = wordCounts.writeStream
  .outputMode("complete")
  .format("console")
  .start()

wordCounts.explain()  // additional codes


But it failed with “AnalysisException: Queries with streaming sources must
be executed with writeStream.start()”?


Thanks
Chang