Re: Some doubts about window start time and end time

[Dawid Wysakowicz]

Hi Jun,

First of all how do you actually get the ranges? TimeWindow#getStart
returns a long, which you must've interpreted somehow. I will try to
describe my suspicions. I think the core problem is that you pass the
input in one timezone, but interpret in a different one. (the processing
time uses UTC timestamps).?0?2 This would explain the shift.

The windows are always aligned in UTC time, with 6h window you get:
[-6:00- 0:00], [0:00 - 6:00], [6:00 - 12:00], ... but if you shift it to
your local time zone (I assume +8) you get: [2:00-8:00], [8:00, 14:00], ...

If you perform the same operation for 1h window you get (in UTC):
[-8:00, -7:00], ..., [-1:00, 0:00],[0:00-1:00], ... and after shifting:
[-8:00, -7:00] becomes [0:00 -1:00], which is what you described, but of
course it contains different records than the [0:00-1:00] interpreted in
UTC.

On the second topic of the offset. The offset actually means an offset
within a window. You can shift the window a bit, but you cannot shift
the whole timeline. That's why the offset must be smaller than the
window size.

Best,

Dawid



On 27/11/2019 11:44, Jun Zhang wrote:
>
> Hi,Caizhi :
> 1.if I add offset ,
> window(TumblingProcessingTimeWindows.of(Time.hours(6),Time.hours(-8)))
> ?0?2 ?0?2it wil get a error: TumblingProcessingTimeWindows parameters must
> satisfy abs(offset) < size
> 2.If it is caused by do not adding an offset, then why the same code,
> I set the window size to be an hour and there is no problem, and set
> the window size to six hours will be a problem?
>
>
> On 11/27/2019 18:21??Caizhi Weng
>  wrote??
>
> Hi Jun,
>
> You have to specify an offset when defining the windows. According
> to the Java docs of TumblingProcessingTimeWindows: "/if you are
> living in somewhere which is not using UTC??00:00 time/,/such as
> China which is using UTC+08:00/,/and you want a time window with
> size of one day/,/and window begins at every 00:00:00 of local
> time/,/you may use {/*/@code
> /*/of/(/Time.days/(/1/),/Time.hours/(/-8/))/}. The parameter of
> offset is {/*/@code /*/Time.hours/(/-8/))/} since UTC+08:00 is 8
> hours earlier than UTC time./"
>
> Does this solve the problem?
>
> Jun Zhang <825875...@qq.com >
> ??2019??11??27?? 6:03??
>
>
>
> Hi??Caizhi ??
>
> the code like this :
>
>
> dataStream
> .keyBy(??device")
> .window(TumblingProcessingTimeWindows.of(Time.hours(6)))
> .trigger(ContinuousProcessingTimeTrigger.of(Time.seconds(5)))
> 
> ?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2
>  ?0?2 .aggregate(new MyAggre(), new
> WindowResultFunction()) ?0?2
> ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 ?0?2 
> ?0?2 ?0?2 ?0?2.print();
>
> I add a trigger for quick output
>
>
> On 11/27/2019 17:54??Caizhi Weng
> wrote??
>
> Hi Jun,
>
> How do you define your window? Could you please show us
> the code?
>
> Thanks.
>
> Jun Zhang <825875...@qq.com >
> ??2019??11??27?? 5:22??
>
> ,
> Hi:
> I defined a Tumbling window, I set the time size to
> one hour, and the resulting windows are [00: 00:
> 00-01: 00: 00], [01: 00: 00-02: 00: 00]. 
> This meets my expectations, but when I set the time
> size to 6 hours, the resulting window size is [02: 00:
> 00-08: 00: 00], [08: 00: 00-14: 00: 00], [14: 00:
> 00-20: 00: 00] ...
> But my expected window size is [00: 00: 00-06: 00:
> 00], [06: 00: 00-12: 00: 00] ...
> Is it right to get such a window result?
>
> thanks
>
>


signature.asc
Description: OpenPGP digital signature

Re: Some doubts about window start time and end time

[Jun Zhang]

Hi,Caizhi :
1.if I add offset , 
window(TumblingProcessingTimeWindows.of(Time.hours(6),Time.hours(-8)))
 it wil get a error: TumblingProcessingTimeWindows parameters must 
satisfy abs(offset) < size 
2.If it is caused by do not adding an offset, then why the same code, I set the 
window size to be an hour and there is no problem, and set the window size to 
six hours will be a problem?
   
  

 
 
 
 On 11/27/2019 18:21??Caizhi Weng

Re: Some doubts about window start time and end time

[Caizhi Weng]

Hi Jun,

You have to specify an offset when defining the windows. According to the
Java docs of TumblingProcessingTimeWindows: "*if you are living in
somewhere which is not using UTC±00:00 time*,* such as China which is using
UTC+08:00*,*and you want a time window with size of one day*,* and window
begins at every 00:00:00 of local time*,*you may use {**@code **of*(
*Time.days*(*1*),*Time.hours*(*-8*))*}. The parameter of offset is {**@code
**Time.hours*(*-8*))*} since UTC+08:00 is 8 hours earlier than UTC time.*"

Does this solve the problem?

Jun Zhang <825875...@qq.com> 于2019年11月27日周三 下午6:03写道：

>
>
> Hi，Caizhi ：
>
> the code like this :
>
>
> dataStream
> .keyBy(“device")
> .window(TumblingProcessingTimeWindows.of(Time.hours(6)))
> .trigger(ContinuousProcessingTimeTrigger.of(Time.seconds(5)))
> .aggregate(new MyAggre(), new
> WindowResultFunction())
>  .print();
>
> I add a trigger for quick output
>
>
> On 11/27/2019 17:54，Caizhi Weng
>  wrote：
>
> Hi Jun,
>
> How do you define your window? Could you please show us the code?
>
> Thanks.
>
> Jun Zhang <825875...@qq.com> 于2019年11月27日周三 下午5:22写道：
>
>> ,
>> Hi:
>> I defined a Tumbling window, I set the time size to one hour, and the
>> resulting windows are [00: 00: 00-01: 00: 00], [01: 00: 00-02: 00: 00]. 
>> This meets my expectations, but when I set the time size to 6 hours, the
>> resulting window size is [02: 00: 00-08: 00: 00], [08: 00: 00-14: 00: 00],
>> [14: 00: 00-20: 00: 00] ...
>> But my expected window size is [00: 00: 00-06: 00: 00], [06: 00: 00-12:
>> 00: 00] ...
>> Is it right to get such a window result?
>>
>> thanks
>>
>>
>>

Re: Some doubts about window start time and end time

[Jun Zhang]

Hi??Caizhi ??


the code like this :




dataStream
.keyBy(??device")
.window(TumblingProcessingTimeWindows.of(Time.hours(6)))
.trigger(ContinuousProcessingTimeTrigger.of(Time.seconds(5)))


 .aggregate(new MyAggre(), new WindowResultFunction())  
   
 .print();



I add a trigger for quick output




On 11/27/2019 17:54??Caizhi Weng

Re: Some doubts about window start time and end time

[Caizhi Weng]

Hi Jun,

How do you define your window? Could you please show us the code?

Thanks.

Jun Zhang <825875...@qq.com> 于2019年11月27日周三 下午5:22写道：

> ,
> Hi:
> I defined a Tumbling window, I set the time size to one hour, and the
> resulting windows are [00: 00: 00-01: 00: 00], [01: 00: 00-02: 00: 00]. 
> This meets my expectations, but when I set the time size to 6 hours, the
> resulting window size is [02: 00: 00-08: 00: 00], [08: 00: 00-14: 00: 00],
> [14: 00: 00-20: 00: 00] ...
> But my expected window size is [00: 00: 00-06: 00: 00], [06: 00: 00-12:
> 00: 00] ...
> Is it right to get such a window result?
>
> thanks
>
>
>

Some doubts about window start time and end time

[Jun Zhang]

,  
Hi:
I defined a Tumbling window, I set the time size to one hour, and the resulting 
windows are [00: 00: 00-01: 00: 00], [01: 00: 00-02: 00: 00]. 
This meets my expectations, but when I set the time size to 6 hours, the 
resulting window size is [02: 00: 00-08: 00: 00], [08: 00: 00-14: 00: 00], [14: 
00: 00-20: 00: 00] ...
But my expected window size is [00: 00: 00-06: 00: 00], [06: 00: 00-12: 00: 00] 
...
Is it right to get such a window result?



thanks