title: How to write Spark SQL batch job results to the Apache Druid?
body: <p>I want to write Spark batch results data to the Apache Druid. I know Druid has <strong><em>native batch ingestions</em></strong> such as <code>index_parallel</code>. Druid runs Map-Reduce jobs in the same cluster. But I only want to use Druid as a data storage. I want to aggregate data external Spark cluster, then send it to the Druid cluster. </p>
  
  <p>Druid has <code>Tranquility</code> for real-time ingestion. I can send batch data using Tranquility, but this is not efficient. How can I send batch results to the Druid efficiently? </p>