apache/spark — pull request #2686 by liancheng (2014-10-07 02:09:11+00:00)
Title: [SPARK-3824][SQL] Sets in-memory table default storage level to MEMORY_AND_DISK

Using `MEMORY_AND_DISK` as default storage level for in-memory table caching. Due to the in-memory columnar representation, recomputing an in-memory cached table partitions can be very expensive.