Returns an estimated size of this relation in bytes.
Returns an estimated size of this relation in bytes. This information is used by the planner to decided when it is safe to broadcast a relation and can be overridden by sources that know the size ahead of time. By default, the system will assume that tables are too large to broadcast. This method will be called multiple times during query planning and thus should not perform expensive operations for each invocation.
::DeveloperApi:: A BaseRelation that can eliminate unneeded columns and filter using selected predicates before producing an RDD containing all matching tuples as Row objects.
The pushed down filters are currently purely an optimization as they will all be evaluated again. This means it is safe to use them with methods that produce false positives such as filtering partitions based on a bloom filter.