[rules-users] Field value is different when and then section, very strange. Is it mvel vs java issue

kina06 reachkn6 at gmail.com
Tue Oct 30 15:27:46 EDT 2012


Davide,
   Thanks a bunch!!

/"When an object is insert in the working memory, it will be matched against
all rules: some of them will become active, because the logic expressed in
there applies to your fact, some others will not. 
So, Wolfgang has pointed out an important detail: make sure that there is a
strong logic correlation 
(implication) between the conditions in the LHS and the actions in the RHS,
so that you don't execute 
unwanted actions. 

Given the fact that evaluation and execution take place in two different
stages (see Esteban's email 
for details), a change in the object's status MAY invalidate the conditions,
but the engine needs to know about that: by the time a rule is executed, it
won't go back and double-check the conditions unless told so. "/
>> Yes above information is very valuable, that evaluation and execution is
>> done in two steps/stages, I feel this understanding is very critical, now
>> I see why an update is necessary to let the process know that it has
>> reevaulate rules, but at the same token I should be careful with my when
>> condition, it should be very specific.

/there are cases when your same fact is shared between two separate
contexts/ 
>> Yes, my rules fall under this category.

Thank you all!! All I'm trying to do is understand how it works rather than
just get a solution and move on.




--
View this message in context: http://drools.46999.n3.nabble.com/Field-value-is-different-when-and-then-section-very-strange-Is-it-mvel-vs-java-issue-tp4020550p4020588.html
Sent from the Drools: User forum mailing list archive at Nabble.com.


More information about the rules-users mailing list