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https://issues.apache.org/jira/browse/FLINK-5658?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15882488#comment-15882488
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ASF GitHub Bot commented on FLINK-5658:
---------------------------------------

Github user sunjincheng121 commented on a diff in the pull request:

    https://github.com/apache/flink/pull/3386#discussion_r102925177
  
    --- Diff: 
flink-streaming-java/src/main/java/org/apache/flink/streaming/runtime/operators/windowing/WindowOperator.java
 ---
    @@ -563,7 +590,14 @@ private void emitWindowContents(W window, ACC 
contents) throws Exception {
         * of the given window.
         */
        protected boolean isLate(W window) {
    -           return (windowAssigner.isEventTime() && (cleanupTime(window) <= 
internalTimerService.currentWatermark()));
    +           if (windowAssigner.isEventTime()) {
    +                   if (windowAssigner instanceof 
GlobalEventTimeRowWindowAssigner) {
    +                           return 
windowAssignerContext.getCurrentElementTime() < 
windowAssignerContext.getCurrentMaxTime();
    --- End diff --
    
    I think this logic does not work very well if the data arrives is out of 
order.  How do you think?


> 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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