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From Alberto Ramón <a.ramonporto...@gmail.com>
Subject Memory on Aggr
Date Mon, 07 Nov 2016 20:33:50 GMT
>From "Relational Queries on Data Stream in Apache Flink" > Bounday Memory
Requirements
(
https://docs.google.com/document/d/1qVVt_16kdaZQ8RTfA_f4konQPW4tnl8THw6rzGUdaqU/edit#
)


*SELECT user, page, COUNT(page) AS pCntFROM pageviews*

*GROUP BY user, page*

*-Versus-*


*SELECT user, page, COUNT(page) AS pCntFROM pageviews*

*WHERE rowtime BETWEEN now() - INTERVAL '1' HOUR AND now() // only last
hour*

*GROUP BY user, page*

I understand:

   - Not use WaterMark to pre-calculate agrr, and save memory
   - Store all events "as is" until the end of window

are My assumptions true ?

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