- From: Andrew Newman <andrewfnewman@gmail.com>
- Date: Sun, 23 Mar 2008 20:53:42 +1000
- To: "Lee Feigenbaum" <lee@thefigtrees.net>
- Cc: "Richard Newman" <rnewman@twinql.com>, andy.seaborne@hp.com, "Arjohn Kampman" <arjohn.kampman@aduna-software.com>, "public-rdf-dawg-comments@w3.org" <public-rdf-dawg-comments@w3.org>
On 20/03/2008, Lee Feigenbaum <lee@thefigtrees.net> wrote:
> This part _seems_ to indicate to me that you believe there to be at
> least one query and RDF dataset for which the SPARQL specification is
> not sufficient to determine what results an implementation should
> return. Could you please provide such a query, a dataset for the query,
> and the point at which you see an ambiguity in the specification as to
> how to evaluate the query against the dataset? (I understand that you
> may be saying that this applies to a large class of queries & datasets;
> I'm only asking for one example, please.)
>
Yes. From the test page
(http://www.w3.org/2001/sw/DataAccess/tests/r2.html) - I can't find
any empty group pattern queries. While we're at it maybe add the one
for unbound variable in the project clause as an error too.
Here are the new tests.
Test 1
=====
Data:
http://www.w3.org/2001/sw/DataAccess/tests/data-r2/graph/data-g1.ttl
Query:
SELECT * WHERE { ?s ?p ?o UNION {} }
Results:
http://www.w3.org/2001/sw/DataAccess/tests/data-r2/graph/graph-05.ttl
Test 2
=====
Data:
http://www.w3.org/2001/sw/DataAccess/tests/data-r2/graph/data-g1.ttl
Query:
SELECT * WHERE { ?s ?p ?o . {} }
Results (this is suppose to represent empty):
<?xml version="1.0"?>
<sparql
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:xs="http://www.w3.org/2001/XMLSchema#"
xmlns="http://www.w3.org/2005/sparql-results#" >
<head>
<variable name="s"/>
<variable name="p"/>
<variable name="o"/>
</head>
<results>
</results>
</sparql>
Test 3
=====
Negative syntax test.
SELECT ?x WHERE { ?s ?p ?o }
Received on Sunday, 23 March 2008 10:54:18 UTC