[rules-users] Searching a list - Is Drools the answer?

Drools User drools2030 at gmail.com
Sun Apr 17 23:53:03 EDT 2011


I have been using Drools for several years, but just with constraints
(rules) on 1 set of objects at a time. Think many rules, few facts in a
stateless session. I have been given a new project at the office which
requires having about 10-100k facts and few rules. These 10k facts would be
basically constants, a list of things I need to search on each request. I
would then need to load a single object, based on a request to see if my
request object matched the list. It is somewhat a simple search, but I need
to be able to inject aliases and search partial matches in addition to exact
matches. A generic example:

List:
Object 1 (FirstName=John, LastName=Smith)
Object 2 (FirstName=Will, LastName=Smith)
Object 3 (FirstName=Jon, LastName=Smith)

Request/Use Case:
LastName=Smith, would return all 3 objects, but marked as single match
LastName=Smith, Firstname =John, Would return object 1, as exact double
match, and Object 3 a nickname double match
LastName=Smith, Firstname =J, Would return object 1 and 3, as partial match

In the second request, I need to run all names through a nickname DB/list to
explode the name into multiple search patterns. Possibly using (
http://code.google.com/p/nickname-and-diminutive-names-lookup/)

Hopefully that explains a bit about the problem.

So to the question, there are a few ways to solve this. The simplest is just
SQL from a DB, but this proves to be slow to search all the ways I need. I
need sub second response times. An in memory DB is another possible solution
we are looking at. Not to think of Drools as the golden hammer, but this
smells like something I can use Drools for. My first thought was to load the
"List" as facts into a stateful session. My concern is wouldn't I need N
copies of the list loaded to have N threads? This would be inefficient if
so. I know rules aren't copied per working memory, but is there a way to
create a master working memory for facts to use?

So my second thought is to convert my List into rules so they would only be
stored once in the system, regardless of number of threads using the engine.

What do you guys think, am I on the right track with this? Is Drools a good
way to do this or is there something better I have overlooked?

Thank you for taking the time.
-Drools user
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20110417/f9662d31/attachment.html 


More information about the rules-users mailing list