Hi Slava, I'm forwarding your message to our new mailing list at Apache: [email protected] You can subscribe to the list by sending an (empty) email to: [email protected]. We are planning to shut down the stratosphere-dev@googlegroups soon.
Regarding your question: When using the Tuples, you don't need to specify a keySelector. It is sufficient to specify the ID(s) of the keys: http://stratosphere-javadocs.github.io/eu/stratosphere/api/java/DataSet.html#groupBy(int.. .) So you should be able to do a ".groupBy(0,3,4)" Robert ---------- Forwarded message ---------- From: Vyacheslav Zholudev <[email protected]> Date: Thu, Jun 12, 2014 at 12:17 AM Subject: [stratosphere-dev] Grouping by a tuple To: [email protected] Hi, Being used to the Hive grouping like "GROUP BY userId, productId, year" I'm wondering what's the best way to do it in Stratosphere? The groupBy's KeySelector implies that a Comparable object is returned, however, the obvious choice like TupleN is not comparable. In primitive cases I would prefer to avoid introducing comparable extra entities for grouping tuples of "primitive" types. Would it make sense to introduce "ComparableTupleN<T1 extends Comparable<? extends T1>, ..., Tn extends Comparable<? extends Tn>>"? Or am I missing the obvious way in a Stratosphere way? Thanks, Vyacheslav -- You received this message because you are subscribed to the Google Groups "stratosphere-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. Visit this group at http://groups.google.com/group/stratosphere-dev. For more options, visit https://groups.google.com/d/optout.
