RE: [rules-users] Order of columns and of constraints

Hi Dirk, I understand (but could be wrong!) that the ordering of patterns does influence the performance of the rules. I assume that the RETE network is created from top to bottom as the rules are parsed. Therefore more restrictive constraints at the start of a rule will be parsed first and hence be nearer the root of the RETE network consequentially optimising the identification of activations. I suspect the "Rules Team" will give a more scientific explanation ;-) With kind regards, Mike -----Original Message----- From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Dirk Bergstrom Sent: 31 May 2007 03:27 To: Rules Users List Subject: [rules-users] Order of columns and of constraints Does the order of columns in the rule definition, and the order of constraints within a column matter? For a given rule, I know which test is most likely to fail, and (probably) which one is most "expensive" in terms of processing time (eg. 'someCollection contains $var' is more expensive than 'field == "literal"'). I'd like to put the fail-fast tests up front, and the expensive ones last. Does that actually work in Drools? Can I "optimize" my rules by juggling the order of the columns and constraints? -- Dirk Bergstrom dirk(a)juniper.net _____________________________________________ Juniper Networks Inc., Computer Geek Tel: 408.745.3182 Fax: 408.745.8905 _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users