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Posted to user@flink.apache.org by zhen li <li...@hotmail.com> on 2018/10/17 10:34:27 UTC
Manual trigger the window in fold operator or incremental aggregation
Hi all:
How can I trigger the window manually in fold operator or incremental aggregation? For example, when some conditions is meet，althouth the count window or time window is not reach
Re: Manual trigger the window in fold operator or incremental aggregation
Posted by Niels van Kaam <ni...@vankaam.net>.
Sorry, I would not know that. I have worked with custom triggers, but
haven't actually had to implement a custom window function yet.
By looking at the interfaces I would not say that is possible.
Niels
On Wed, Oct 17, 2018 at 2:18 PM Ahmad Hassan <ah...@gmail.com> wrote:
> Hi Niels,
>
> Can we distinguish within apply function of 'RichWindowFunction' whether
> it was called due to onElement trigger call or onProcessingtime trigger
> call of a custom Trigger ?
>
> Thanks!
>
> On Wed, 17 Oct 2018 at 12:51, Niels van Kaam <ni...@vankaam.net> wrote:
>
>> Hi Zhen Li,
>>
>> You can control when a windowed stream emits data with "Triggers". See:
>> https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html#triggers
>>
>> Flink comes with a couple of default triggers, but you can also create
>> your own by implementing
>> https://ci.apache.org/projects/flink/flink-docs-stable/api/java/org/apache/flink/streaming/api/windowing/triggers/Trigger.html
>> .
>>
>> Note that this does not change the window, but just causes the
>> windowedstream to emit intermediate results to the next operator.
>>
>> Does this answer your question?
>>
>> Cheers,
>> Niels
>>
>> On Wed, Oct 17, 2018 at 12:34 PM zhen li <li...@hotmail.com> wrote:
>>
>>> Hi all:
>>> How can I trigger the window manually in fold operator or
>>> incremental aggregation? For example, when some conditions is meet，althouth
>>> the count window or time window is not reach
>>
>>
Re: Manual trigger the window in fold operator or incremental aggregation
Posted by Dominik Wosiński <wo...@gmail.com>.
Hey Zhen Li,
What are You trying to do exactly? Maybe there is a more suitable method
than manually triggering windows available in Flink.
Best Regards,
Dom.
śr., 24 paź 2018 o 09:25 Dawid Wysakowicz <dw...@apache.org>
napisał(a):
> Hi Zhen Li,
>
> As far as I know that is not possible. For such custom handling I would
> recommend having a look at ProcessFunction[1], where you have access to
> timers and state.
>
> Best,
>
> Dawid
> [1]
> https://ci.apache.org/projects/flink/flink-docs-release-1.6/dev/stream/operators/process_function.html#process-function-low-level-operations
>
> On 17/10/2018 14:18, Ahmad Hassan wrote:
>
> Hi Niels,
>
> Can we distinguish within apply function of 'RichWindowFunction' whether
> it was called due to onElement trigger call or onProcessingtime trigger
> call of a custom Trigger ?
>
> Thanks!
>
> On Wed, 17 Oct 2018 at 12:51, Niels van Kaam <ni...@vankaam.net> wrote:
>
>> Hi Zhen Li,
>>
>> You can control when a windowed stream emits data with "Triggers". See:
>> https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html#triggers
>>
>> Flink comes with a couple of default triggers, but you can also create
>> your own by implementing
>> https://ci.apache.org/projects/flink/flink-docs-stable/api/java/org/apache/flink/streaming/api/windowing/triggers/Trigger.html
>> .
>>
>> Note that this does not change the window, but just causes the
>> windowedstream to emit intermediate results to the next operator.
>>
>> Does this answer your question?
>>
>> Cheers,
>> Niels
>>
>> On Wed, Oct 17, 2018 at 12:34 PM zhen li <li...@hotmail.com> wrote:
>>
>>> Hi all:
>>> How can I trigger the window manually in fold operator or
>>> incremental aggregation? For example, when some conditions is meet，althouth
>>> the count window or time window is not reach
>>
>>
Re: Manual trigger the window in fold operator or incremental
aggregation
Posted by Dawid Wysakowicz <dw...@apache.org>.
Hi Zhen Li,
As far as I know that is not possible. For such custom handling I would
recommend having a look at ProcessFunction[1], where you have access to
timers and state.
Best,
Dawid
[1]
https://ci.apache.org/projects/flink/flink-docs-release-1.6/dev/stream/operators/process_function.html#process-function-low-level-operations
On 17/10/2018 14:18, Ahmad Hassan wrote:
> Hi Niels,
>
> Can we distinguish within apply function of 'RichWindowFunction'
> whether it was called due to onElement trigger call or
> onProcessingtime trigger call of a custom Trigger ?
>
> Thanks!
>
> On Wed, 17 Oct 2018 at 12:51, Niels van Kaam <niels@vankaam.net
> <ma...@vankaam.net>> wrote:
>
> Hi Zhen Li,
>
> You can control when a windowed stream emits data with "Triggers".
> See:
> https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html#triggers
> Flink comes with a couple of default triggers, but you can also
> create your own by implementing
> https://ci.apache.org/projects/flink/flink-docs-stable/api/java/org/apache/flink/streaming/api/windowing/triggers/Trigger.html.
>
> Note that this does not change the window, but just causes the
> windowedstream to emit intermediate results to the next operator.
>
> Does this answer your question?
>
> Cheers,
> Niels
>
> On Wed, Oct 17, 2018 at 12:34 PM zhen li <lizhenmxcz@hotmail.com
> <ma...@hotmail.com>> wrote:
>
> Hi all:
> How can I trigger the window manually in fold operator or
> incremental aggregation? For example, when some conditions is
> meet，althouth the count window or time window is not reach
>
Re: Manual trigger the window in fold operator or incremental aggregation
Posted by Ahmad Hassan <ah...@gmail.com>.
Hi Niels,
Can we distinguish within apply function of 'RichWindowFunction' whether it
was called due to onElement trigger call or onProcessingtime trigger call
of a custom Trigger ?
Thanks!
On Wed, 17 Oct 2018 at 12:51, Niels van Kaam <ni...@vankaam.net> wrote:
> Hi Zhen Li,
>
> You can control when a windowed stream emits data with "Triggers". See:
> https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html#triggers
>
> Flink comes with a couple of default triggers, but you can also create
> your own by implementing
> https://ci.apache.org/projects/flink/flink-docs-stable/api/java/org/apache/flink/streaming/api/windowing/triggers/Trigger.html
> .
>
> Note that this does not change the window, but just causes the
> windowedstream to emit intermediate results to the next operator.
>
> Does this answer your question?
>
> Cheers,
> Niels
>
> On Wed, Oct 17, 2018 at 12:34 PM zhen li <li...@hotmail.com> wrote:
>
>> Hi all:
>> How can I trigger the window manually in fold operator or
>> incremental aggregation? For example, when some conditions is meet，althouth
>> the count window or time window is not reach
>
>
Re: Manual trigger the window in fold operator or incremental aggregation
Posted by Niels van Kaam <ni...@vankaam.net>.
Hi Zhen Li,
You can control when a windowed stream emits data with "Triggers". See:
https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html#triggers
Flink comes with a couple of default triggers, but you can also create your
own by implementing
https://ci.apache.org/projects/flink/flink-docs-stable/api/java/org/apache/flink/streaming/api/windowing/triggers/Trigger.html
.
Note that this does not change the window, but just causes the
windowedstream to emit intermediate results to the next operator.
Does this answer your question?
Cheers,
Niels
On Wed, Oct 17, 2018 at 12:34 PM zhen li <li...@hotmail.com> wrote:
> Hi all:
> How can I trigger the window manually in fold operator or incremental
> aggregation? For example, when some conditions is meet，althouth the count
> window or time window is not reach