WSO2 CEP流计数功能重新启动

Question

I have the following query:

from stream1
select count() as item insert into newStream;

Is it possible to restart the count() function of a stream?

If not, how can I circumvent this? If possible.

Answer 1

If you use count() or any other aggregate function without a window, there's no way to reset the events that get accumulated within that aggregator. For example if you use a window like below, it will reset the counter after receiving 10 events.

from stream1#window.lengthBatch(10)
select count() as item insert into newStream;

However, If you need to reset the counter by sending an parameter to it, (ie count(bool reset) ) you may have to write your own custom aggregate function as described in the following documentation .