Hello, In the case of "sum", you can just specify them one after the other, like:
stream.sum(1).sum(2) This works, because summing the two fields are independent. However, in the case of "keyBy", the information is needed from both fields at the same time to produce the key. Best, Gábor 2016-06-07 14:41 GMT+02:00 Al-Isawi Rami <rami.al-is...@comptel.com>: > Hi, > > Is there any reason why “keyBy" accepts multi-field, while for example “sum” > does not. > > -Rami > Disclaimer: This message and any attachments thereto are intended solely for > the addressed recipient(s) and may contain confidential information. If you > are not the intended recipient, please notify the sender by reply e-mail and > delete the e-mail (including any attachments thereto) without producing, > distributing or retaining any copies thereof. Any review, dissemination or > other use of, or taking of any action in reliance upon, this information by > persons or entities other than the intended recipient(s) is prohibited. Thank > you.
