Hi Edson, Yes, I have been writing and checking the audit log. It shows several activations of the "test" rule, and I've pasted them below if that helps. There are no other activation events with fact handles to [19, 6313, 3681] except for the "test" rule. These two rules intentionally do not have any side effects written in the RHS, specifically to avoid the case that an activation of one rule would somehow lead to a change affecting the LHS of another rule or any other side effects. I load all of the facts before the rules, and no other code is executed except for the KnowledgeSession fireAllRules() method followed by dispose(). <org.drools.audit.event.ActivationLogEvent> <type>4</type> <activationId>test [19, 6313, 3681]</activationId> <rule>test</rule> <declarations>f=Feature.ORF00019(19); hit=org.jcvi.annotation.facts.HmmHit.ORF00019.TIGR00549.ABOVE_TRUSTED.13 836 502(3681); p=FeatureProperty.TIGR00549(6313)</declarations> </org.drools.audit.event.ActivationLogEvent> <org.drools.audit.event.ActivationLogEvent> <type>6</type> <activationId>test [19, 6313, 3681]</activationId> <rule>test</rule> <declarations>f=Feature.ORF00019(19); hit=org.jcvi.annotation.facts.HmmHit.ORF00019.TIGR00549.ABOVE_TRUSTED.13 836 502(3681); p=FeatureProperty.TIGR00549(6313)</declarations> </org.drools.audit.event.ActivationLogEvent> <org.drools.audit.event.ActivationLogEvent> <type>7</type> <activationId>test [19, 6313, 3681]</activationId> <rule>test</rule> <declarations>f=Feature.ORF00019(19); hit=org.jcvi.annotation.facts.HmmHit.ORF00019.TIGR00549.ABOVE_TRUSTED.13 836 502(3681); p=FeatureProperty.TIGR00549(6313)</declarations> </org.drools.audit.event.ActivationLogEvent> Nelson ---------------------------------------------------------------------- Message: 1 Date: Tue, 6 Jul 2010 12:39:22 -0400 From: Edson Tirelli <tirelli(a)post.com&gt; Subject: Re: [rules-users] How is this possible? To: Rules Users List <rules-users(a)lists.jboss.org&gt; Message-ID: <AANLkTik_Ge7ay6M4gcakpUAgccshwCmU7ke2IYNFJhg6(a)mail.gmail.com&gt; Content-Type: text/plain; charset="windows-1252" Nelson, How do you know one rule is firing, but not the other? Are you checking the audit log or using an agenda listener for that? Otherwise, if you think the rule is not firing because of your println in the consequence, you might be looking at the wrong "symptom". There is a huge difference between writing an "if" like that in the consequence of a rule and writing a constraint like "hitId == "TIGR00549"" in the condition of the rule, because the LHS of a rule is evaluated at "insert" time while the RHS is evaluated at the consequence fire time. So, from the information given, trying to imagine a scenario to explain why the syserr in the "test" rule shows up while the one in the first rule doesn't, here is a possible explanation: * You insert the fact HmmHit, it activates both rules, but in a given time, before the "Hmm Hit" rule is fired, the value of hitId changes. In this case, the rule would still fire, but the "if" in the consequence is only evaluated after the change (during consequence fire time) and so evaluates to false, not printing the message. This is a pretty simple use case and we have several customers/users with thousands of rules and millions of facts in a single session and they are not facing anything like you described. So, while a bug is always a possible explanation, we need a way to reproduce your problem in order to give you a proper answer. Edson ******************************************* _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users