Cheng Hao 09265ad7c8 [SPARK-7320] [SQL] Add Cube / Rollup for dataframe ... Add `cube` & `rollup` for DataFrame For example: ```scala testData.rollup($"a" + $"b", $"b").agg(sum($"a" - $"b")) testData.cube($"a" + $"b", $"b").agg(sum($"a" - $"b")) ``` Author: Cheng Hao <hao.cheng@intel.com> Closes #6257 from chenghao-intel/rollup and squashes the following commits: 7302319 [Cheng Hao] cancel the implicit keyword a66e38f [Cheng Hao] remove the unnecessary code changes a2869d4 [Cheng Hao] update the code as comments c441777 [Cheng Hao] update the code as suggested 84c9564 [Cheng Hao] Remove the CubedData & RollupedData 279584c [Cheng Hao] hiden the CubedData & RollupedData ef357e1 [Cheng Hao] Add Cube / Rollup for dataframe		2015-05-20 19:09:47 +08:00
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src	[SPARK-7320] [SQL] Add Cube / Rollup for dataframe	2015-05-20 19:09:47 +08:00
pom.xml	[SPARK-7485] [BUILD] Remove pyspark files from assembly.	2015-05-12 01:39:21 -07:00