group by rollup(("userUnitName","userName"))
-- 当userUnitName 与userName 都一样时,进行求和,并增加一行
group by rollup("userUnitName","userName")
-- 先对(userUnitName,userName)进行分组, 然后对userUnitName进行分组,并且对每一行userUnitName进行求和,并增加一行
Oracle的rollup、cube、grouping sets函数 的详解见下面连接:
https://blog.youkuaiyun.com/huang_xw/article/details/6402396