In CEP you may need sliding time windows. If you want to check for combinations of events or omissions of events in every time window that a particular triggering event belongs to, let's say we have a time-window of one hour and need to update every second, then you have 3600 facts that match just one event. With many events and many event-patterns that need to be checked (subscriptions) you end up with a lot of nodes. This is especially problematic in a real-time setting. Also you may need to consider (and thus store) a history of states of the rete network. This is not natively supported. The following article http://www.rn.inf.tu-dresden.de/uploads/pikm32-walzer.pdf describes the problem pretty well and suggests an extension on the rete algorithm to deal with a sliding time window operator. I am curious if there are other implementations or workarounds in Jess that work well. Martijn
But this is not a "Rete" issue. Rete is about managing facts for rules containing patterns that result in boolean values. You can invent any number of relational operators; they are just frontent syntactic sugar where otherwise you have to use a call to a boolean function. -W On 14 March 2011 15:29, Tromm, Martijn <martijn.tr...@ordina.nl<mailto:martijn.tr...@ordina.nl>> wrote: Hi, Does anybody have any experience with complex event processing in Jess? One of the shortcomings of Rete is that there is no native support for temporal operators besides matching on timestamps and checking time differences Disclaimer Dit bericht met eventuele bijlagen is vertrouwelijk en uitsluitend bestemd voor de geadresseerde. Indien u niet de bedoelde ontvanger bent, wordt u verzocht de afzender te waarschuwen en dit bericht met eventuele bijlagen direct te verwijderen en/of te vernietigen. Het is niet toegestaan dit bericht en eventuele bijlagen te vermenigvuldigen, door te sturen, openbaar te maken, op te slaan of op andere wijze te gebruiken. Ordina N.V. en/of haar groepsmaatschappijen accepteren geen verantwoordelijkheid of aansprakelijkheid voor schade die voortvloeit uit de inhoud en/of de verzending van dit bericht. This e-mail and any attachments are confidential and are solely intended for the addressee. If you are not the intended recipient, please notify the sender and delete and/or destroy this message and any attachments immediately. It is prohibited to copy, to distribute, to disclose or to use this e-mail and any attachments in any other way. Ordina N.V. and/or its group companies do not accept any responsibility nor liability for any damage resulting from the content of and/or the transmission of this message.
