- From: Paul Vincent <pvincent@tibco.com>
- Date: Wed, 3 Sep 2008 16:10:10 -0700
- To: "Alex Kozlenkov" <alex.kozlenkov@betfair.com>
- Cc: <public-rif-wg@w3.org>
Ah - obviously I misunderstood your requirement / use case: - you get multiple events of the same type with the same content - only some of these are appropriate in certain patterns. You'll need to specify the discriminator in more detail: in other words, for << we want this sequence to invalidate a simple C<=AB pattern >>, *when* do you want to invalidate this pattern? e.g. It could be that only 1 C event is allowed in a certain time window. Paul Vincent TIBCO | Business Optimization | Business Rules & CEP > -----Original Message----- > From: Alex Kozlenkov [mailto:alex.kozlenkov@betfair.com] > Sent: 03 September 2008 22:08 > To: Paul Vincent > Cc: public-rif-wg@w3.org > Subject: RE: Congratulations on Christian's and co. courage > > I am referring to legitimate events that must not be de-duplicated as > they are used in various ways in the engine. The approach with negation > does not scale with the number of condition event increasing to even > 5-10, which would create a heck of a rule. The approach with cleansing > is very awkward, error-prone and does not scale either. > > -----Original Message----- > From: Paul Vincent [mailto:pvincent@tibco.com] > Sent: 03 September 2008 22:00 > To: Alex Kozlenkov > Cc: public-rif-wg@w3.org > Subject: RE: Congratulations on Christian's and co. courage > > So you have identical content in events A1, A2. > Then event B occurs. > Apply rule C <= AB > You get C1, C2. > > Unless... you apply a higher priority rule to "remove" / invalidate A2 > (or cleanse the event stream first in a separate process / ruleset). > > Or if dupes are common, you might handle it in your rules: > C <= AB & !(AAB) > > [In TIBCO's CEP-rule engine, and without regard to RIF sensitivities, we > might handle this by running event de-duping in the "event > pre-processor" - allows for event handling before activating the rule > engine. In a RIF context, or another BRE, I would simply have a separate > de-dedupe ruleset and run that before the C <= AB rule(set)]. > > Hope this helps. > > Paul Vincent > TIBCO | Business Optimization | Business Rules & CEP > > > > -----Original Message----- > > From: Alex Kozlenkov [mailto:alex.kozlenkov@betfair.com] > > Sent: 03 September 2008 21:44 > > To: Paul Vincent > > Cc: public-rif-wg@w3.org > > Subject: RE: Congratulations on Christian's and co. courage > > > > What happens if the duplicate events A;A are truly different, with > > different timestamps, and we want this sequence to invalidate a simple > > C<=AB pattern? The rule happily emitting two detections given the > input > > A;A;B may be something entirely incorrect. > > > > -----Original Message----- > > From: Paul Vincent [mailto:pvincent@tibco.com] > > Sent: 03 September 2008 20:48 > > To: Alex Kozlenkov > > Cc: public-rif-wg@w3.org > > Subject: RE: Congratulations on Christian's and co. courage > > Importance: Low > > > > As this qu is CEP-related, I guess I should give an answer too. > > > > 1. Gary is correct from the logical perspective, of course. > > > > 2. Events can be duplicates either in their transmission or their > > meaning: > > > > In middleware terms, it is normally the responsibility of the > middleware > > to ensure duplicates don't happen! > > > > In event terms, though, I can receive multiple events which signify > the > > same information. For example I may be polling a hardware device and > > getting the same result, or someone may hit the "Buy" button in their > > web browser twice. > > > > In the latter case, there are 2 order events but they represent the > same > > order, so there might be some rules / logic in the system to handle > this > > (de-dupe). Those rules could presumably be represented in RIF, e.g. > > > > If ?BetA and ?BetB occur within 5 secs of each other AND sameContent( > > ?BetA, ?BetB) > > Then // assume BetB is a dupe > > ?BetB.dupe = TRUE, ?BetB.IsDupeOf = ?BetA, ?BetB.Status = invalid. > > > > ... > > > > Paul Vincent > > TIBCO | Business Optimization | Business Rules & CEP > > > > > > > -----Original Message----- > > > From: public-rif-wg-request@w3.org > > [mailto:public-rif-wg-request@w3.org] > > > On Behalf Of Gary Hallmark > > > Sent: 03 September 2008 18:31 > > > To: Alex Kozlenkov > > > Cc: public-rif-wg@w3.org > > > Subject: Re: Congratulations on Christian's and co. courage > > > > > > > > > no such thing as 2 identical facts. Relations are sets. Frames > have > > a > > > unique OID. > > > Note that PRD currently has no way to create a new object, and that > is > > a > > > problem we need to fix. > > > > > > Alex Kozlenkov wrote: > > > > And one more comment about the minimality I'm discussing in my > > previous > > > > post. This is not an idle question. If there exist two identical > > facts, > > > > will there be two actions executed or only one? In the language > > dialect > > > > for event processing that the JBoss guys are developing, I was > > trying to > > > > understand whether A<=B,C given B and C matching incoming events, > if > > C > > > > was detected twice, would the action A be executed twice? What I > > mean is > > > > that there may be situation when we want to only detect one > > situation so > > > > that the sequence of events CCB should execute A only once. > > > > > > > > > > > > > > > ________________________________________________________________________ > > > > In order to protect our email recipients, Betfair Group use > SkyScan > > from > > > > MessageLabs to scan all Incoming and Outgoing mail for viruses. > > > > > > > > > > > ________________________________________________________________________ > > > > > > > > > > > > > > > ________________________________________________________________________ > > In order to protect our email recipients, Betfair Group use SkyScan > from > > MessageLabs to scan all Incoming and Outgoing mail for viruses. > > > > > ________________________________________________________________________ > > ________________________________________________________________________ > In order to protect our email recipients, Betfair Group use SkyScan from > MessageLabs to scan all Incoming and Outgoing mail for viruses. > > ________________________________________________________________________
Received on Wednesday, 3 September 2008 23:11:10 UTC