[rules-users] Using RDF and RDF Schema to enable dinamic data model

[Wolfgang Laun]

On 22/03/2012, Jackson Cunha <jackson.cereb at gmail.com> wrote:
> This message is primarily directed to Davide and Salaboy.
>

Nevertheless...

> For do that, our idea is represent the data model using rdf and rdf schema,
> applying rdf instances directly on drools knowledge sessions.
>
> We believe that use of rdf instances will turn the rule writing more
> difficult. To address this issue, we are planning buila a DSL using antrl.

Anything that comes close to the expressive power of DRL is going to be
quite a lot of work. For one thing, DRL comprises almost all of Java's
syntax defining "expression". Then, there are the extensions for
writing Conditional Elements. Last, but not least, even RHS may have
to be parsed for converting statements accessing the RDF facts, unless
you manage to permit updates against the basic RDF facts.

>
> Given that, I'd like your opinion about some questions:
>
> - What is your opinion about using rdf instances as facts in knowledge
> sessions?

Drools is designed to work with bean-style pojos. Using
subject-predicate-object triples to represent a bean with n fields
requires n facts instead of one which will increase your memory
footprint. There's also some performance impact to be expected as
insert/modify/retract on smaller units will inevitably cause more work
by the Engine with activation creation and deletion.

> - What do you think the idea of ??using dsl to facilitate rule writing
> involving instances of RDF?

The compiler will have to avoid antipatterns in the generated LHS code.


> - You see any other alternative to make data model dynamic using or not
> ontologies?

Have you looked into the newly introduced feature of traits?

-W

>
> Thanks in advance.
>
> ----------------------------------------------------------------------------------------------------------------
> Jackson Cunha Cassimiro (CereB)
> Bacharel em Ciencia da Computação - UFPI
> MSN: jackson.cereb at gmail.com
> Telefone Móvel +55 86 9928 1251
> Analista de Sistemas - Infoway - http://www.infoway-pi.com.br
> Missão Infoway - "Influenciar a Gestão de Sistemas de Saúde através de
> e-health"
>
> ("A vida é um combate que os fracos abate, aos bravos, aos fortes só pode
> exaltar" - Canção do Tamoio, Gonçalves Dias)
> ----------------------------------------------------------------------------------------------------------------
>