In spark streaming, what is the difference between foreach and foreachRDD

Question

For example, how would

x.foreach(rdd => rdd.cache())

be different from

x.foreachRDD(rdd => rdd.cache())

Note that x is a DStream here.

Answer 1

There is no difference in work, foreach() uses foreachRDD. foreach() was deprecated and in Spark 2.0 this function is removed