Spark 2.0 Scala - RDD.toDF()

Yes, you should import sqlContext implicits like that:

val sqlContext = //create sqlContext

import sqlContext.implicits._

val df = RDD.toDF()

Before you call to "toDF" in your RDDs

It's coming from here:

Spark 2 API

Explanation: if you import sqlContext.implicits._, you have a implicit method to convert RDD to DataSetHolder (rddToDataSetHolder), then you call toDF on the DataSetHolder