Hi Pablo, I agree with your analysis here especially the last one regarding evolution of archetypes.
Regards, Rong On 3 October 2011 16:23, pablo pazos <pazospablo at hotmail.com> wrote: > Hi everyone, > > I've been studying how to simplify the ITEM_STRUCTURE model to enhance the > persistence performance of our Open EHR-Gen project > (http://code.google.com/p/open-ehr-gen-framework). > > Now I'm reaching a point in which I doubt about the necessity of ITEM_SINGLE > in the RM (as a subclass of ITEM_STRUCTURE) and I want to expose some > arguments and hear your comments about it. > > Semantic argument: As I understand ITEM_SINGLE, the semantics of this class > are the same as an ITEM_LIST or ITEM_TREE with only one ELEMENT, I mean > that: the semantics of ITEM_SINGLE is just a matter of cardinality (=1). > > Practical argument: in practice, an ITEM_SINGLE is like using an ELEMENT as > an ITEM_STRUCTURE. And if we have only TREEs, LISTs and TABLEs, the > interface of each class can be the same, like: getItems(), setItems(), the > ITEM_SINGLE breaks that with getItem() and setItem(). > > Evolution argument: If I have an archetype with an ITEM_SINGLE, but the > concept modeled with this archetype needs to change adding more nodes to the > archetype, I need to change the ITEM_SINGLE to another ITEM_STRUCTURE, but > if the archetype is modeled with an ITEM_TREE, I can add any nodes without > changing the ITEM_STRUCTURE type. I think this way is more simple to create > new archetypes with backwards compatibility. > > > What do you think? > > -- > Kind regards, > Ing. Pablo Pazos Guti?rrez > LinkedIn: http://uy.linkedin.com/in/pablopazosgutierrez > Blog: http://informatica-medica.blogspot.com/ > Twitter: http://twitter.com/ppazos > _______________________________________________ > openEHR-clinical mailing list > openEHR-clinical at openehr.org > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-clinical >
