Github user chenghao-intel commented on the pull request:

    https://github.com/apache/spark/pull/3964#issuecomment-69522110
  
    The SQL enhanced aggregation syntax may looks like in HiveContext as:
    ```
    GROUP BY expression list WITH ROLLUP
    GROUP BY expression list WITH CUBE
    GROUP BY expression list, GROUPING SETS (expression list2)
    ```
    See 
https://cwiki.apache.org/confluence/display/Hive/Enhanced+Aggregation,+Cube,+Grouping+and+Rollup
    Currently in logical analysis and execution, we follows the Hive's 
specification, however, in SQL99, it also supports the format like:
    ```
    GROUP BY expression list, GROUPING SETS (expression list2), expression list3
    GROUP BY expression list, CUBE(expression list2), expression list3
    GROUP BY expression list, ROLLUP(expression list2), expression list3
    ```
    The `grouping column reference list` is optionally required by `CUBE` and 
`ROLLUP` (http://savage.net.au/SQL/sql-99.bnf.html) , and there are some 
additional work need to be done on the `Logical Node` and `Analyzer` to support 
the semantics like for this.
    
    Probably we'd better implement the Hive-Like format first in SQLContext, 
what do you think?



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