Persist this RDD with the default storage level (MEMORY_ONLY
).
Return a new RDD containing only the elements that satisfy a predicate.
Set this RDD's storage level to persist its values across operations after the first time it is computed.
Set this RDD's storage level to persist its values across operations after the first time it is computed. Can only be called once on each RDD.
Return a sampled subset of this RDD.
Return the union of this RDD and another one.
Return the union of this RDD and another one. Any identical elements will appear multiple
times (use .distinct()
to eliminate them).
Note: the schema
of a union is this RDD's schema.