apache/spark — pull request #2215 by liancheng (2014-08-30 09:51:37+00:00)
Title: [SPARK-2973][SQL] Lightweight SQL commands without distributed jobs when calling .collect()

By overriding `executeCollect()` in physical plan classes of all commands, we can avoid to kick off a distributed job when collecting result of a SQL command, e.g. `sql("SET").collect()`.