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https://issues.apache.org/jira/browse/CALCITE-3271?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Rui Wang updated CALCITE-3271:
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    Issue Type: New Feature  (was: Improvement)

> Table-valued function windowing and EMIT syntax support in Calcite
> ------------------------------------------------------------------
>
>                 Key: CALCITE-3271
>                 URL: https://issues.apache.org/jira/browse/CALCITE-3271
>             Project: Calcite
>          Issue Type: New Feature
>          Components: core
>    Affects Versions: 1.20.0
>            Reporter: Danny Chen
>            Assignee: Rui Wang
>            Priority: Major
>
> Copied from the mailing list:
> Calcite has not implemented the syntax in that paper. I would support an 
> effort to add it (unsurprising, since I am a co-author of that paper).
> EMIT STREAM is equivalent to the current SELECT STREAM syntax.
> There is no equivalent in current Calcite of the EMIT AFTER WATERMARK, or 
> EMIT STREAM AFTER DELAY.
> HOP, TUMBLE and SESSION are supported in Calcite’s SQL parser, but following 
> the paper would be replaced with a table function call. We could need to add 
> HOP, TUMBLE and SESSION table functions. We would also need to make the 
> system aware of how watermarks flow through these table functions (an area 
> that the paper does not go into).
> Julian
> From Rui Wang
> Table-value function windowing means implementing TUMBLE/TOP/SESSION by 
> table-value function. As table value functions, TUMBLE/HOP/SESSION assigns 
> each row of input table to one or more intervals containing the specified 
> watermarked event timestamp column. Those intervals are determined by the 
> same way of current windowing support in Calcite: TUMBLE generates fixed 
> length, non-overlapping intervals; HOP generates fixed length, overlapping 
> intervals; SESSION generates sessionized intervals. The output table of this 
> proposed implementation has all columns of input table plus two additional 
> columns wstart and wend, which represent the start and the end of the 
> interval respectively.
> possible gaps in current Calcite:
> 1. TABLE parameter support in table-value function.
> 2. DESCRIPTOR parameter support in table-value function.
> 3. TUMBLE/TOP/SESSION implemented as built-in table-value function.
> 4. EMIT AFTER WATERMARK and EMIT STREAM AFTER DELAY. 



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