Geoffrey,
We briefly discussed about having specialized nodes for operations
like count(), average(), max(), etc, but if I remember correctly, we
didn't came to a conclusion.
The new version (in trunk) does have "accumulate" that provides the
functionality, but being a general purpose conditional element, it can't
provide optimizations like the one you described, that would not be
difficult to implement in a specialized node.
So, even incurring the risk of making the language fat, I would agree
in adding that functionallity. Lets hear the others.
[]s
Edson
Geoffrey De Smet wrote:
I am logically asserting a bunch of Routeobjects:
new Route(Object cause, int distance)
and I need the sum of all the distances of all the Routes.
so after the rules are fired I can fetch all Routes and sum the
distances.
Problem is... in my use case I am constantly (like +1k times a second)
changing one little fact, firing all rules and decide which fact to
change next based on the sum of the distances. Talk about stressing
drools's forward-chaining :)
So by constantly recalculating the sum of those distances starting
from 0, it loses a huge amount of scalability.
It would be a lot better if a sum would be calculated like this:
nextSum = lastSum - distanceFromAnyRetractedRoutes +
distanceFromAnyAssertedRoutes;
This would mean that the rules engine would need to support some sort
of sum query's.
What do you think? Is this feasible and in the scope of drools enough
to create a long term feature request in jira for this?
Thanks.
--
---
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3124-6000
Mobile: +55 11 9218-4151
JBoss, a division of Red Hat @ www.jboss.com
IT executives: Red Hat still #1 for value
http://www.redhat.com/promo/vendor/
---------------------------------------------------------------------
To unsubscribe from this list please visit:
http://xircles.codehaus.org/manage_email
