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https://issues.apache.org/jira/browse/FLINK-5658?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15900925#comment-15900925
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sunjincheng edited comment on FLINK-5658 at 3/8/17 8:42 AM:
------------------------------------------------------------

HI [~Yuhong_kyo] Let me share some ideas about this.

First of all,
     I suggest use processFunction to implement this JIRA. Because 
processFunction can manager `TimerService` which can control trigger window 
calculation. It's very powerful.( Actually, mentioned in the [~fhueske]'s [ML | 
https://mail.google.com/mail/#sent/159cbf3f0bf209aa]) 

secondly,
    I suggest manage StateBackend in processFunction, then STATE together with 
the TIMER, may be able to solve this problem.
Maybe we need a more detailed design, here is just a suggestion, for reference 
only. I believe that if there is a mistake here, [~fhueske] will do the 
correction.

Best,
SunJincheng



was (Author: sunjincheng121):
HI [~Yuhong_kyo] Let me share some ideas about this.

First of all,
     I suggest use processFunction to implement this JIRA. Because 
processFunction can manager `TimerService` which can control trigger window 
calculation. It's very powerful.( Actually, mentioned in the [~fhueske]'s [ML | 
https://mail.google.com/mail/#sent/159cbf3f0bf209aa] 

secondly,
    I suggest manage StateBackend in processFunction, then STATE together with 
the TIMER, may be able to solve this problem.
Maybe we need a more detailed design, here is just a suggestion, for reference 
only. I believe that if there is a mistake here, [~fhueske] will do the 
correction.

Best,
SunJincheng


> Add event time OVER RANGE BETWEEN UNBOUNDED PRECEDING aggregation to SQL
> ------------------------------------------------------------------------
>
>                 Key: FLINK-5658
>                 URL: https://issues.apache.org/jira/browse/FLINK-5658
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Table API & SQL
>            Reporter: Fabian Hueske
>            Assignee: Yuhong Hong
>
> The goal of this issue is to add support for OVER RANGE aggregations on event 
> time streams to the SQL interface.
> Queries similar to the following should be supported:
> {code}
> SELECT 
>   a, 
>   SUM(b) OVER (PARTITION BY c ORDER BY rowTime() RANGE BETWEEN UNBOUNDED 
> PRECEDING AND CURRENT ROW) AS sumB,
>   MIN(b) OVER (PARTITION BY c ORDER BY rowTime() RANGE BETWEEN UNBOUNDED 
> PRECEDING AND CURRENT ROW) AS minB
> FROM myStream
> {code}
> The following restrictions should initially apply:
> - All OVER clauses in the same SELECT clause must be exactly the same.
> - The PARTITION BY clause is optional (no partitioning results in single 
> threaded execution).
> - The ORDER BY clause may only have rowTime() as parameter. rowTime() is a 
> parameterless scalar function that just indicates processing time mode.
> - bounded PRECEDING is not supported (see FLINK-5655)
> - FOLLOWING is not supported.
> The restrictions will be resolved in follow up issues. If we find that some 
> of the restrictions are trivial to address, we can add the functionality in 
> this issue as well.
> This issue includes:
> - Design of the DataStream operator to compute OVER ROW aggregates
> - Translation from Calcite's RelNode representation (LogicalProject with 
> RexOver expression).



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