Hi All,
I saw Till's blog preparation. It will be a very helpful blog. I hope that some other blogs that explain how it works will come soon :-) I have a question on followedBy pattern matching semantic. >From the documentation https://ci.apache.org/projects/flink/flink-docs-master/apis/streaming/libs/cep.html , <citaton> Non-strict contiguity means that other events are allowed to occur in-between two matching events. A non-strict contiguity pattern state can be created via the followedBy method. Pattern<Event, ?> nonStrictNext = start.followedBy("middle"); </citation> I try to use Till's examples in the blog, to understand the semantic of followedBy -- First question. Say, I have sequence of temperatures in a time window that corresponds to the within clause (say in 20 minutes). TemperatureEvent(40) , OtherEvent(...), TemperatureEvent(30), TemperatureEvent(50), OtherEvent(...), TemperatureEvent(70), TemperatureEvent(65), TemperatureEvent(60) say I want to match two TemperatureEvents whose temperatures > 35. What will be the matches in this case ? - Will TemperatureEvent(40) , TemperatureEvent(50), match ? (because we have TemperatureEvent(30) at time 3 that does not match. - Will TemperatureEvent(40) , TemperatureEvent(70) match ? (because the pair matches also the specification of pattern , the difference is we have TemperatureEvent(50) which happened before TempertureEvent(70) ). Similar question for TemperatureEvent(40) - TemperatureEvent(65) and TemperatureEvent(50)-TemperatureEvent(65) etc. pairs. -- Second question. For next (and also for followedBy) , I have also questions regarding example above: Will TemperatureEvent(70), TemperatureEvent(65) and TemperatureEvent(65), TemperatureEvent(60) be returned , or the second pair is no longer returned because TemperatureEvent(65) has been used in the first pair ? Is there a way to define the different sequence semantics for the two questions I asked above ? Thanks, Anwar.
