Returns a placeholder for a physical plan that executes plan
.
Returns a placeholder for a physical plan that executes plan
. This placeholder will be
filled in automatically by the QueryPlanner using the other execution strategies that are
available.
Converts a logical plan into zero or more SparkPlans. This API is exposed for experimenting with the query planner and is not designed to be stable across spark releases. Developers writing libraries should instead consider using the stable APIs provided in org.apache.spark.sql.sources