A proposal for an RDF query language

This was also sent to the RDF interest group ... sorry
for cross-postings...
Dear RDF-Logic members,
we would like to announce our proposal for an RDF query language, RQL.

You can find our paper at:
PDF: http://www.ics.forth.gr/proj/isst/RDF/RQL/rql.pdf
PS:  http://www.ics.forth.gr/proj/isst/RDF/RQL/rql.ps
DVI: http://www.ics.forth.gr/proj/isst/RDF/RQL/rql.dvi
(math symbols in the html version require symbol fonts - 
usually found in PCs)
A short abstract follows.

We really invite interested readers to send us their comments
and/or suggestions.

Best regards
Greg Karvounarakis


                 Querying Community Web Portals

Information systems such as organizational memories, vertical
aggregators, infomediaries, etc. are expected to play a central 
role in the 21st-century economy by enabling the development and
maintenance of specific communities of interest (e.g., enterprise,
professional, trading) on corporate intranets or the Web. Such 
Community Web Portals essentially provide the means to select, 
classify and access, in a semantically meaningful and ubiquitous
way various information resources (e.g., sites, documents, data)
for diverse target audiences (corporate, inter-enterprise, 
e-marketplace, etc.). 

Yet, in commercial software for deploying Community Portals,
querying is still limited to full-text (or attribute-value)
retrieval and more advanced information-seeking needs require
navigational access.  Furthermore, recent Web standards for
describing resources (see the W3C Metadata Activity: RDF/ RDF 
Schema) are completely ignored. Moreover, standard (relational 
or object) databases are too rigid for capturing the 
peculiarities of RDF descriptions and schemas.

Motivated by the above issues, we propose a new data model and a
query language for RDF descriptions and schemas. Our language, 
called $RQL$, relies on a formal graph model, that captures the
RDF modeling primitives, also providing a richer type system, and
permits the interpretation of RDF descriptions by means of one or
more schemas. In this context, $RQL$ adapts the functionality of
semistructured query languages to the peculiarities of RDF but 
also extends this functionality in order to query RDF schemas.
The novelty of $RQL$ lies in its ability to smoothly switch
between schema and data querying while exploiting - in a
transparent way - the taxonomies of labels and multiple
classification of resources.

Received on Tuesday, 7 November 2000 12:58:41 UTC