Thanks for reporting back. Glad it worked for you. Actually sum with partitioning behaviour is same in oracle too. On 10 Aug 2016 03:01, "Jon Barksdale" <jon.barksd...@gmail.com> wrote:
> Hi Santoshakhilesh, > > I'd seen that already, but I was trying to avoid using rdds to perform > this calculation. > > @Ayan, it seems I was mistaken, and doing a sum(b) over(order by b) > totally works. I guess I expected the windowing with sum to work more like > oracle. Thanks for the suggestion :) > > Thank you both for your help, > > Jon > > On Tue, Aug 9, 2016 at 3:01 AM Santoshakhilesh < > santosh.akhil...@huawei.com> wrote: > >> You could check following link. >> >> http://stackoverflow.com/questions/35154267/how-to- >> compute-cumulative-sum-using-spark >> >> >> >> *From:* Jon Barksdale [mailto:jon.barksd...@gmail.com] >> *Sent:* 09 August 2016 08:21 >> *To:* ayan guha >> *Cc:* user >> *Subject:* Re: Cumulative Sum function using Dataset API >> >> >> >> I don't think that would work properly, and would probably just give me >> the sum for each partition. I'll give it a try when I get home just to be >> certain. >> >> To maybe explain the intent better, if I have a column (pre sorted) of >> (1,2,3,4), then the cumulative sum would return (1,3,6,10). >> >> Does that make sense? Naturally, if ordering a sum turns it into a >> cumulative sum, I'll gladly use that :) >> >> Jon >> >> On Mon, Aug 8, 2016 at 4:55 PM ayan guha <guha.a...@gmail.com> wrote: >> >> You mean you are not able to use sum(col) over (partition by key order by >> some_col) ? >> >> >> >> On Tue, Aug 9, 2016 at 9:53 AM, jon <jon.barksd...@gmail.com> wrote: >> >> Hi all, >> >> I'm trying to write a function that calculates a cumulative sum as a >> column >> using the Dataset API, and I'm a little stuck on the implementation. From >> what I can tell, UserDefinedAggregateFunctions don't seem to support >> windowing clauses, which I think I need for this use case. If I write a >> function that extends from AggregateWindowFunction, I end up needing >> classes >> that are package private to the sql package, so I need to make my function >> under the org.apache.spark.sql package, which just feels wrong. >> >> I've also considered writing a custom transformer, but haven't spend as >> much >> time reading through the code, so I don't know how easy or hard that would >> be. >> >> TLDR; What's the best way to write a function that returns a value for >> every >> row, but has mutable state, and gets row in a specific order? >> >> Does anyone have any ideas, or examples? >> >> Thanks, >> >> Jon >> >> >> >> >> -- >> View this message in context: http://apache-spark-user-list. >> 1001560.n3.nabble.com/Cumulative-Sum-function-using- >> Dataset-API-tp27496.html >> Sent from the Apache Spark User List mailing list archive at Nabble.com. >> >> --------------------------------------------------------------------- >> To unsubscribe e-mail: user-unsubscr...@spark.apache.org >> >> >> >> >> >> -- >> >> Best Regards, >> Ayan Guha >> >>
