Thanks David, I will look at your references 👍🏻
> On 19 Mar 2020, at 09:51, David Anderson <da...@ververica.com
> <mailto:da...@ververica.com>> wrote:
>
> Humberto,
>
> Although Flink CEP lacks notFollowedBy at the end of a Pattern, there is a
> way to implement this by exploiting the timeout feature.
>
> The Flink training includes an exercise [1] where the objective is to
> identify taxi rides with a START event that is not followed by an END event
> within two hours. You'll find a solution to this exercise that uses CEP in
> [2].
>
> [1] https://training.ververica.com/exercises/longRides.html
> <https://training.ververica.com/exercises/longRides.html>
> [2]
> https://github.com/ververica/flink-training-exercises/blob/master/src/main/java/com/ververica/flinktraining/solutions/datastream_java/cep/LongRidesCEPSolution.java
>
> <https://github.com/ververica/flink-training-exercises/blob/master/src/main/java/com/ververica/flinktraining/solutions/datastream_java/cep/LongRidesCEPSolution.java>
>
> Best,
> David
>
>
>
> On Thu, Mar 19, 2020 at 4:41 AM Zhijiang <wangzhijiang...@aliyun.com
> <mailto:wangzhijiang...@aliyun.com>> wrote:
> Hi Humberto,
>
> I guess Fuji is familiar with Flink CEP and he can answer your proposed
> question. I already cc him.
>
> Best,
> Zhijiang
>
> ------------------------------------------------------------------
> From:Humberto Rodriguez Avila <rhumber...@outlook.com
> <mailto:rhumber...@outlook.com>>
> Send Time:2020 Mar. 18 (Wed.) 17:31
> To:user <user@flink.apache.org <mailto:user@flink.apache.org>>
> Subject:FlinkCEP - Detect absence of a certain event
>
> In the documentation of FlinkCEP, I found that I can enforce that a
> particular event doesn't occur between two other events using notFollowedBy
> or notNext.
>
> However, I was wondering If I could detect the absence of a certain event
> after a time X. For example, if an event A is not followed by another event A
> within 10 seconds, fire an alert or do something.
>
> Could be possible to define a FlinkCEP pattern to capture that situation?
>
> Thanks in advance, Humberto
>
>
