[
https://issues.apache.org/jira/browse/FLINK-5658?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15875533#comment-15875533
]
Yuhong Hong commented on FLINK-5658:
------------------------------------
Hi [~fhueske] & [~wheat9], i saw haohui have already commit the rowtime()
feature, but still no cover the LogicalWindowRelNode situation, as how to
distinguish rowtime() and proctime(), i want to do like this:
LogicalProject(with RexOver expr) -> [normalize rule(ProjectToWindow)]
->CalciteLogicalWindow(input = LogicalProject(with rowtime() func)) ->
(normalize rule(FlinkLogicalWindowRule)) ->FlinkLogicalWindow(input =
LogicalProject, isEventtime=true/false, window=CalciteLogicalWindow)
Cause after normalize period, the rowtime() function will be replaced by
generator code according to ReduceExpressionsRule, so we can only check whether
eventtime or proctime before apply ReduceExpressionsRule in normalize period.
So i want to add an FlinkLogicalWindow which include the CalciteLogicalWindow
and an isEventtime attribute, and add a additional rule(FlinkLogicalWindowRule)
to do the transform.
In FlinkLogicalWindowRule, i will check according whether the function operator
is EventTimeExtractor or ProcTimeExtractor.
What do you think? or if already have solution, please let me know.
> 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).
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
