- From: Damian Steer <d.steer@bristol.ac.uk>
- Date: Sat, 21 Aug 2010 09:20:19 +0100
- To: Olaf Hartig <hartig@informatik.hu-berlin.de>
- Cc: public-sparql-dev@w3.org
On 21 Aug 2010, at 08:50, Olaf Hartig wrote:
> My question is: Is something similar possible with CONSTRUCT queries?
> Something that I could use to create -for instance- an RDF triple
>
> <http://example.org/Bob> ex:ageAfterBDay 12 .
>
> from the triple
>
> <http://example.org/Bob> ex:age 11 .
>
> by increasing the value bound to the ?year variable.
>
> I studied the latest working draft of SPARQL 1.1 but I couldn't find something.
You can do this in SPARQL 1.1 currently using subqueries:
construct { <http://example.org/Bob> ex:ageAfterBDay ?nextYear }
{ select (?year + 1 AS ?nextYear) { <http://example.org/Bob> ex:age ?year } }
Which, even in this simple case, has a syntax only a mother could love.
I believe assignment [1] has been discussed, which is like ARQ's LET. [2]
construct { <http://example.org/Bob> ex:ageAfterBDay ?nextYear }
{ <http://example.org/Bob> ex:age ?year . ( let ?nextYear := ?year + 1 ) }
Damian
[1] <http://www.w3.org/2009/sparql/wiki/Feature:Assignment>
[2] <http://jena.sourceforge.net/ARQ/assignment.html>
Received on Saturday, 21 August 2010 08:20:55 UTC