[
https://issues.apache.org/jira/browse/FLINK-6228?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15957817#comment-15957817
]
Fabian Hueske commented on FLINK-6228:
--------------------------------------
That's true. It is not possible to define Tumble Rows windows with SQL over.
However, Tumble Time (which should be much more common) is possible by
partitioning on the (ceiled) time attribute (as in my previous example).
My concern is that we overload the API with too many window options which are
hard to understand and rarely used in practice.
For Flink 1.3, I would suggest to focus on adding syntax to the Table API to
specify SQL over windows because these can be currently executed. I don't think
we should add many more new window types (including translation and execution)
for the next release. Of course the row window syntax of the Table API should
be designed such that it can be later easily extended without breaking existing
code.
What do you think [~sunjincheng121]?
> Integrating the OVER windows in the Table API
> ---------------------------------------------
>
> Key: FLINK-6228
> URL: https://issues.apache.org/jira/browse/FLINK-6228
> Project: Flink
> Issue Type: Sub-task
> Components: Table API & SQL
> Reporter: sunjincheng
> Assignee: sunjincheng
>
> Syntax:
> {code}
> table
> .overWindows(
> (Rows|Range [ partitionBy value_expression , ... [ n ]] [ orderBy
> order_by_expression]
> (preceding
> UNBOUNDED|value_specification.(rows|milli|second|minute|hour|day|month|year)|CURRENTROW)
> [following
> UNBOUNDED|value_specification.(rows|milli|second|minute|hour|day|month|year)|CURRENTROW]
> as alias,...[n])
> )
> .select( [col1,...[n]], (agg(col1) OVER overWindowAlias, … [n])
> {code}
> Implement restrictions:
> * 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 Before the
> [FLINK-5884|https://issues.apache.org/jira/browse/FLINK-5884] implementation
> orderBy may only have ‘rowtime/’proctime(for stream)/‘specific-time-field(for
> batch).
> * FOLLOWING is not supported.
> I will soon add a user interface design document.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
