- From: Steve Harris <S.W.Harris@ecs.soton.ac.uk>
- Date: Thu, 23 Mar 2006 10:50:52 +0000
- To: Semantic Web <semantic-web@w3.org>
On Thu, Mar 23, 2006 at 11:30:51 +0100, Henry Story wrote:
> <#blue> god:timeslice [ tr:inCalendarClockDataType
> "2006-03-23T10:00:00Z"^^xsd:dateTime;
> god:temperature "22"^^xzd:celsius ],
> [ tr:inCalendarClockDataType
> "2006-03-23T10:00:00Z"^^xsd:dateTime;
> god:temperature "12"^^xzd:celsius ];
I had a very similar problem in representing trivial provenance-ish
information (when certain files were parsed, what parse errors there were
etc.) inside my triple store. Currently there is a hack updates a triple like
foo:graphId :lastUpdated "2006-01-01T01:01:01"^^xsd:dateTime .
when each graph is reread, and always adds a
foo:graphId :updated "2006-01-01T01:01:01"^^xsd:dateTime .
I'm thinking of replacing this with a SPAQRQL query/rule that can always find
the most recent one, along the lines of
SELECT ?last
WHERE { foo:graphId :updated ?last }
ORDER BY DESC(?last)
LIMIT 1
The graphs have to be done one-by-one as theres no GROUP BY equivalent in
SPARQL.
- Steve
Received on Thursday, 23 March 2006 10:51:10 UTC