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A present for Guy Fawkes night

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Fri, 5 Nov 2004 13:39:25 -0000
Message-ID: <8D5B24B83C6A2E4B9E7EE5FA82627DC94D3082@sdcexcea01.emea.cpqcorp.net>
To: "RDF Data Access Working Group" <public-rdf-dawg@w3.org>

Simon and I were discussing interoperability testing after the telecon.

It is traditional on Bonfire Night (Guy Fawkes night) in the UK to let
off fireworks to celebrate a failed attempt to blow up the houses of
Parliament.  Fireworks include SPARQLers.  So it is with some
trepidation, I have put up a SPARQL server based on some rather unproven
code.

What works: (and I use "works" in the loosest possible sense)
+ SELECT (RDF results only), CONSTRUCT (maybe), DESCRIBE (maybe)

What doesn't work:
- Only results in RDF support - no XML result format yet (needs code
refactoring)
- ASK (no result format)
- Illegal queries are likely to cause nasty things to happen in the
server.
- Everything, when internal errors use up all the servelet threads 


Examples:

http://sparql.org/books?lang=SPARQL&query=SELECT%20$v%20WHERE%20(%20$x%2
0$p%20$v%20)%20AND%20$v%20=~%20/Phoenix/

i.e.
SELECT $v
WHERE ( $x $p $v) AND $v =~ /Phoenix/



http://sparql.org/books?lang=SPARQL&query=PREFIX%20dc:%20%20%3Chttp://pu
rl.org/dc/elements/1.1/%3E%20SELECT%20$title%20WHERE%20(?x%20dc:title%20
$title)

PREFIX dc:  <http://purl.org/dc/elements/1.1/>
SELECT $title
WHERE (?x dc:title $title)



http://sparql.org/books?lang=SPARQL&query=DESCRIBE%20%3Chttp://example.o
rg/book/book1%3E

DESCRIBE <http://example.org/book/book1>


Protocol:

HTTP request must specify the language (lang=) and the query string
(query=)
Languages are "SPARQL" or "http://jena.hpl.hp.com/2003/07/query/SPARQL"


In a browser, the results will come back text/plain for simple display.
You can ask for application/rdf+xml as well.

The code is in 
cvs.sourceforge.net:/cvsroot/joseki/Joseki3
  and
cvs.sourceforge.net:/cvsroot/jena2/BRQL (but the query engine is called
ARQ).

	Andy
Received on Friday, 5 November 2004 13:39:58 GMT

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