1.[ISSUE #569](https://github.com/sharding-sphere/sharding-sphere/issues/569) Failed to parse SQL for Oracle when ROWNUM is not at end
1.[ISSUE #628](https://github.com/sharding-sphere/sharding-sphere/issues/628) Support data type jsonb for PostgreSQL
1.[ISSUE #646](https://github.com/sharding-sphere/sharding-sphere/issues/646) When aliases in `SELECT ITEMS` correspond to the real column names of `GROUP BY` or `ORDER BY`, there is no need to generate derived columns