- From: Kendall Clark <kendall@monkeyfist.com>
- Date: Thu, 6 May 2004 18:18:10 -0400
- To: Rob Shearer <Rob.Shearer@networkinference.com>
- Cc: Kendall Clark <kendall@monkeyfist.com>, public-rdf-dawg@w3.org
On Thu, May 06, 2004 at 12:32:09PM -0700, Rob Shearer wrote: > Is this proposed for the query language, or for the protocol? I realize > that requirements for both are in scope, but I'm curious what the intent > of the requirement is. I had in mind for the query language. You could put the names of the graphs into protocol, but that seems a strange choice. > In SQL, for example, selection of the database is left to protocol, > while selection of table(s) is part of the query language. That's an unusable analogy, IMO. > If we're talking about aggregating a bunch of separate RDF repositories, > this seems clearly out of scope. First, I didn't say a *word* about "RDF repositories". I said multiple graphs; either querying each graph and unioning the results, or unioning the graphs then executing the query against it. That's got nothing whatever to do with RDF repositories (which is a function of how we *name* the multiple graphs, a position I didn't take in the requirement). > The aggregation of multiple > repositories is nothing but a new repository. Sure, but that's not my requirement. > How repositories are > formed or composed is an architecural issue that is going to cost us a > year if we really do it the right way. Let's not do it--if you want to > write a query client which touches a dozen different repositories, then > write an app that joins them all into a local virtual repository and > then query that. Well, "write it yourself" is feasible, but standardization is a good thing. > The fact that your implementation of the repository > implements the query language in this complex way shouldn't change what > the language is. (Again, we're standardizing what results are right and > wrong, not how you get those results.) Well, I did carefully craft the requirement such that it was or was meant to be optional. Given that the existing universe of RDF storage servers has a wide range of capabilities, something like conformance levels seems inevitable. But, again, just so I'm clear, I asked for multigraph, not multirepository query, which strikes me as an important distinction to keep in mind. Kendall Clark
Received on Thursday, 6 May 2004 18:19:19 UTC