rules are just querries over data, like a database view.
Ask yourself this. If you asserted those two objects, A1 and A2, into a database and you had two views V1 and V2. How would you make V1 select A1 and V2 select A2?

When you have the  answer for  that, it'll apply to Drools too.

Mark
Massi Gmail wrote:

ok

 

But i think I do not need to differentiate them.

 

I try to explain it better.

 

I have got a set of "Contract" class Facts. All of them inserted into the working memory.

 

But Just one of them is the "main contract", all the others all "related contracts".

 

So , when i write a rule I need to distinguish between a "main contract" (which is unique along the session)

and a "related contract".

 

I should write rules like the followings:

 

when

    $mc: Contract() from maincontract

then

    #rule fired over "the" main contract

end

 

when

   $rc: Contract() from relatedcontract

then

   #rule fired over "a" related contract

end

I think the only solution to do that is to make "maincontract" and "relatedcontracr" globals.

But, if I make them globals, then the rule engine will not be notified about their changes and

I do want it to be notified about it.

 

Should I make them "globals" and "facts" as well?

Can globals be inserted into the WM as well? Is it too horrible? :D

 

Thank u anyway.

 

Massi

 

----- Original Message -----

From: Edson Tirelli

To: Rules Users List

Sent: Saturday, January 05, 2008 12:00 PM

Subject: Re: [rules-users] Checking fact "id"

   What attribute differentiates A1 from A2?
   Such scenarios usually are solved by an additional constraint...

   []s
   Edson

2008/1/4, Massi Gmail < mmquelo@gmail.com>:

 

Hi guys,

 

Now I am strugglin' with "fact id checking"  or whatever we can call it.... :D

 

Let's take into account the followong scenario:

 

I have class A (it's just a name) javabeans to be inserted into the WM.

 

I define two objects of class A: A1 and A2.

 

Somewhere I do "insert(A1)" and "insert(A2)" ( let's say I do it in the same package of R1 and R2..see below...)

 

Then I define two different rules R1 and R2 that reason over class "A" facts  (let's say R1 and R2 are in the same package) .

 

The point is....  I want R1 to fire only on A1 and R2 only on A2.

 

Is that possible in drools? Is there a sort of "fact id" I can reason over?

 

I do not think globals will be of any help, cause in the guide i have read that globals should never be used within LHS.

We should never reason over globals.

 

Let me know.

 

Massi

 

 

_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users

--
  Edson Tirelli
  JBoss Drools Core Development
  Office: +55 11 3529-6000
  Mobile: +55 11 9287-5646
  JBoss, a division of Red Hat @ www.jboss.com

---

_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users

_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
  

_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users