I'd definitely suggest this approach. Compiling DRL files into a knowledge base is very expensive and something you want to avoid doing as much as possible and probably wouldn't come anywhere close to meeting your performance requirements! Thomas From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Michael Anstis Sent: 17 March 2011 07:52 To: Rules Users List Subject: Re: [rules-users] drools design question You could hold them all in a single KnowledgeBase with "State", "FactorY" and "FactorX" as Facts themselves checked in the Rules' RHS. You could still have multiple DRL files (to aid authoring and maintenance) but load them all at once. The RETE network shares nodes for patterns shared across multiple rules. If your DRLs therefore share RHS patterns (e.g. simplistically State XX premium for criteria A = 100, State YY premium for criteria A = 110) the "criteria" patterns will be shared. With kind regards, Mike 2011/3/17 Esteban Aliverti <esteban.aliverti@gmail.com<mailto:esteban.aliverti@gmail.com>> You could also use drools (maybe a decision table) to select the different drl files. Best regards, El mar 16, 2011 8:24 p.m., "marunam" <sutavis@gmail.com<mailto:sutavis@gmail.com>> escribió: Hi, We are developing an insurance application and we have decided to use drool rules for our business rules Now, we could have global business rules(applies to all states), specific to state, specific to factor X, specific to factor Y etc. This way we are expecting many drl files. Now, when the application runs, we would know the values for state, factor X, factor Y etc. and using these values we would determine(using database) which drl files to load dynamically and just run the rules in those drls. Is this approach recommended? Do you have any suggestions? Thanks -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/drools-design-questio... Sent from the Drools - User mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users@lists.jboss.org<mailto:rules-users@lists.jboss.org> https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ rules-users mailing list rules-users@lists.jboss.org<mailto:rules-users@lists.jboss.org> https://lists.jboss.org/mailman/listinfo/rules-users ________________________________ ************************************************************************************** This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster(a)nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary. NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00 **************************************************************************************

Actually what you want is that only the rules from the DRLs that you want are activated and their consequences run (a subtle but important distinction). Put another way it doesn't matter how many rules are in the knowledge base and evaluated as long as only the rules you want are matched. There are two main approaches you could do to control this. The first is to use agenda groups with rules in different DRLs being in different agenda groups, this then lets you control which groups consequences are run and in what order to. Another approach is to introduce some additional facts into the working memory - "EnabledRuleGroup(String groupName)". The first condition in each rule would then be the statement "exists EnabledRuleGroup(name =="myDlrFilenameXYZ") Then only rules matching the statement would be evaluated. There are probably other variations around this too - things like agenda filters to filter out the activations you don't want. Thomas ************************************************************************************** This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster(a)nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary. NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00 **************************************************************************************