Bryan --

You wrote....

Along a similar vein, did the survey [[1]] cover any "query languages" that
were achieved through tunneling a restricted set of Prolog?

The Internet Business Logic system answers all 14 questions in [1].

The set of logic programs that it handles is neither a superset nor a subset of what Prolog can do.  Roughly, it's datalog with stratified negation, safe recursion, plus some arithmetic, string manipulation, and aggregations.  It compiles automatically into SQL when necessary.

You can run the 14 questions, and browse the rules that support them, by pointing a browser to .  Click on Internet Business Logic, then on the GO button.  Select RDFQueryLangComparison1 , then -- at the top of the page -- "Go to View or Change the Agent". 

The Help buttons show how to run the questions, and how to get explanations of the answers.  There are also tutorials for a gentle introduction.

HTH.  Thanks in advance for comments.    -- Adrian

[1]           A Comparison of RDF Query Languages
               by Peter Haase, Jeen Broekstra, Andreas Eberhart, and Raphael Volz

At 06:19 AM 5/12/04 -0400, you wrote:


Along a similar vein, did the survey cover any "query languages" that
were achieved through tunneling a restricted set of Prolog?


-----Original Message-----
Sent: 5/11/2004 10:46 PM
Subject: Wilbur Query Language [was: RE: A Comparison of RDF Query

Another query language possibly worth adding to the comparison is that
of the Wilbur Semantic Web Toolkit (dubbed "WQL"). I have written an
analysis of WQL's capabilities vis-a-vis the recently published
comparison and its 14 "tests". The draft is available here:

In summary, I consider two separate languages: "Plain" WQL, using only
the Wilbur query API, and WQL+CL, where "Plain" WQL query results are
manipulated using simple Common Lisp scripting. WQL was designed to be
integrated to Common Lisp as an access mechanism. This, and the fact
that Common Lisp, through the function EVAL, allows the dynamic runtime
execution of arbitrary expressions, justifies the consideration of
WQL+CL as a "query language".

"Plain" WQL is capable of satisfying a subset of the tests, but WQL+CL
can successfully evaluate *all* tests (albeit some queries are a bit
cumbersome :-). Details are included in the above paper.

Questions and comments are welcome.


        - Ora

Ora Lassila
Research Fellow, Nokia Research Center

-----Original Message-----
[]On Behalf Of ext
Sent: Friday, April 30, 2004 6:41 AM
To: Andreas Eberhart
Cc:;;;;;;;;;; Raphael Volz;;
Subject: Re: A Comparison of RDF Query Languages

Related to the recent work of the RDF Data Access Working Group [1], we
have compared six proposals for RDF query languages.

interesting work; to this regard, you might also want not to skip W3C's
Metalog (cf. ).

On the criteria in [2], obviously one might add many different
others as well. Given DAWG's scope, DB-like ops like joins etc might
profitably be included in the list. It would be also nice to express
those use cases in terms of abstract properties, rather than single
use cases: this will help better shaping the requirements document,
keeping a high level of abstraction and generality.