[rules-users] 'from accumulate' doesn't work on multiple colu mns?..

[Edson Tirelli]

   Vlad,

   We really appreciate help. I think it is like 3-4 days work for 
someone that does not know the codebase, but it is a good learning 
opportunity for Drools internals and its workings. Just show up in the 
IRC and we can talk about it.

    Regards,
     Edson

Olenin, Vladimir (MOH) wrote:

>Thanks, Edson. That explains it. Regarding your #1 point, I can try to help,
>especially if it's smth that won't require digging deeply into DROOLS
>implementation details (and would help me to implement the rule I mentioned
>in the previous post :) )... How much time do you think it will take
>providing I'm not familiar with DROOLS codebase? (DROOLS dev-t environment
>setup + this feature implementation)
>
>I'm subscribed to dev-t list (from what I recall), so we can move this
>discussion there...
>
>Thanks,
>
>Vlad
>
>-----Original Message-----
>From: rules-users-bounces at lists.jboss.org
>[mailto:rules-users-bounces at lists.jboss.org] On Behalf Of Edson Tirelli
>Sent: 07 March 2007 17:43
>To: Rules Users List
>Subject: Re: [rules-users] 'from accumulate' doesn't work on multiple
>columns?..
>
>  Vlad,
>
>Trying to answer both of your e-mails in this one.
>
>1. Right now, accumulate supports only a single Pattern (column), as you 
>already realized. That is a limitation we want to remove before the next 
>final release, but it is not done yet. I already know how to fix that, 
>but didn't had the time to do it yet. We are working hard in the BRMS 
>side now. If anyone is willing to help with that, I can provide the 
>instructions on how to do the implementation for that feature.
>
>2. Regarding matching the same fact multiple times in a single tuple, 
>this is a configuration. In 3.0.x, the default is to not allow the same 
>fact to be matched multiple times in a single tuple. In 3.1, the default 
>was changed to allow multiple matches. That is why your tested matched 
>multiple times. This is one of the BIG warnings we need to add to the 
>upgrade documentation.
>
>3. Regarding the distinct, I'm not sure if it would be good to have such 
>"feature". Need further discussion I guess. But on of the ways to work 
>around that is just to have a "driver" fact. I mean, if "f1" means a 
>financial account, for instance, have a Financial Account fact:
>
>rule ...
>when
>FinancialAccount( $id : id )
>Double( doubleValue > 0 ) from accumulate(
>Record( finId == $id, $f2 : f2, $val : value )
>init( double sum = 0; )
>action( sum += ( $f2 < 10 ) ? $val : -$val; )
>result( new Double( sum ) ) )
>then
>// do something
>end
>
>Hope it helps.
>
>[]s
>Edson
>
>Olenin, Vladimir (MOH) wrote:
>
>  
>
>>This is as a follow up for the previous question.... It looks like I 
>>made a wrong assumption that 'accumulate' can work on multiple columns:
>>
>>Integer ( intValue > 0) from accumulate (
>>
>>Record ( f1 == $f1, f2 < 10, $value1 : value )
>>
>>Record ( f1 == $f1, f2 >= 10, $value2 : value )
>>
>>Init ( int sum = 0; ),
>>
>>Action ( sum += $value1 - $value2 ),
>>
>>Result ( new Integer (sum) )
>>
>>)
>>
>>I'm getting an error ('then' is expected or smth like that at the 
>>point where the second 'Record' is defined) and the only way to remove 
>>the error is to declare one and only one Column constraint... So, it is 
>>not possible then to use multiple columns in 'accumulate'? If not, 
>>then it would be even more interesting to get some idea on how to 
>>approach the kind of problem I mentioned in the previous post.....
>>
>>Thanks,
>>
>>Vlad
>>
>>------------------------------------------------------------------------
>>
>>_______________________________________________
>>rules-users mailing list
>>rules-users at lists.jboss.org
>>https://lists.jboss.org/mailman/listinfo/rules-users
>> 
>>
>>    
>>
>
>
>  
>


-- 
 Edson Tirelli
 Software Engineer - JBoss Rules Core Developer
 Office: +55 11 3124-6000
 Mobile: +55 11 9218-4151
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