Re: Datamodel Strawman (ACTION-298)

Dave Reynolds wrote:
> Gary Hallmark wrote:
>>
>> Xpath expressions returns a list of nodes, and nodes can be elements, 
>> attributes, and typed literal values.  So we'd need at minimum some 
>> kind of list in RIF (which we've talked about quite a bit), and I 
>> don't know what you do about elements and attributes.  Forbid them?  
>> Introduce an opaque nodeId?

I had the operational semantics of production rules in mind when I wrote 
that, where only ground rules (rule instances) are evaluated (that is, 
with all variables bound before).

And I had XPath (or a subset of XPath) as a syntax to navigate the data 
when the data model (that the rule interchange refers to) is XML. Not 
necessarily for application to an XML data source.


> So how do existing rule languages handle this at the moment?
> Does everyone have their own data modelling language which they map XML 
> onto? If so what do those modelling languages look like?

The processing model I had in mind is that both end of the interchange 
have their own data modeling language (maybe the same, but that is 
irrelevant : the point is that this should be transparent for the 
interchange). And if they both know the data model that the interchanegd 
RIF document refers to (which is a prerequisite for the interchange), it 
means that they have a mapping between that data model and their own.

And, thus, they will know how to map a in the data that is specified 
according to the common data model into a path specified according to 
their own data model.

Christian

Received on Tuesday, 24 July 2007 14:09:47 UTC