Hi Fabian,
        Is the behavior a bit weird? Because it leads to data inconsistency.

Best,
Henry

> 在 2018年8月21日,下午5:14,Fabian Hueske <fhue...@gmail.com> 写道:
> 
> Hi,
> 
> In the given example, article_id 123 will always remain in the external 
> storage. The state is removed and hence it cannot be retracted anymore.
> Once the state was removed and the count reaches 10, a second record for 
> article_id 123 will be emitted to the data store.
> 
> As soon as you enable state retention and state is needed that was removed, 
> the query result can become inconsistent.
> 
> Best, Fabian
> 
> 2018-08-21 10:52 GMT+02:00 徐涛 <happydexu...@gmail.com 
> <mailto:happydexu...@gmail.com>>:
> Hi Fabian,
>       SELECT article_id FROM praise GROUP BY article_id having count(1)>=10
>       If article_id 123 has 100 praises and remains its state in the dynamic 
> table ,and when the time passed, its state is removed, but later the 
> article_id 123 has never reached to 10 praises.
>       How can other program know that the state is been removed? Because the 
> sink currently has the praises count stored as 100, it is not consistent as 
> the dynamic table.
> 
> Best, 
> Henry
> 
> 
>> 在 2018年8月21日,下午4:16,Fabian Hueske <fhue...@gmail.com 
>> <mailto:fhue...@gmail.com>> 写道:
>> 
>> Hi,
>> 
>> No, it won't. I will simply remove state that has not been accessed for the 
>> configured time but not change the result.
>> For example, if you have a GROUP BY aggregation and the state for a grouping 
>> key is removed, the operator will start a new aggregation if a record with 
>> the removed grouping key arrives.
>> 
>> Idle state retention is not meant to affect the semantics of a query. 
>> The semantics of updating the result should be defined in the query, e.g., 
>> with a WHERE clause that removes all records that are older than 1 day 
>> (note, this is not supported yet).
>> 
>> Best, Fabian
>> 
>> 2018-08-21 10:04 GMT+02:00 徐涛 <happydexu...@gmail.com 
>> <mailto:happydexu...@gmail.com>>:
>> Hi All,
>>         Will idle state retention trigger retract in dynamic table?
>> 
>> Best,
>> Henry
>> 
> 
> 

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