Thanks, Ivan.
My first intuition would say that a sparql query containing
{ _:hidden_bnode skos:prefLabel ?v1_lab .
FILTER (_:hidden_bnode = iri(?:_uri)) }
could be inefficient. Will Virtuoso internally optimize this into a query
equivalent to { $:some_uri skos:prefLabel ?v1_lab. } ?
Lourens
Ivan Mikhailov wrote:
Lourens,
I gues that this will work:
CREATE PROCEDURE VAS_PROPERTY_LABEL (in _uri varchar) {
for (sparql select ?v1_lab where { `iri(?:_uri)` skos:prefLabel ?v1_lab})
do {
RETURN "v1_lab";
}
RETURN _uri;
}
Colon in ?:_uri indicates an external variable, iri() converts a string
(that is a literal) into an IRI reference, backquotes around iri(...)
are syntax syntax so
{ `iri(?:_uri)` skos:prefLabel ?v1_lab}
is equivalent to
{ _:hidden_bnode skos:prefLabel ?v1_lab .
FILTER (_:hidden_bnode = iri(?:_uri)) }
Best Regards,
Ivan Mikhailov
OpenLink Software
http://virtuoso.openlinksw.com
On Sun, 2009-11-29 at 20:29 +0100, Lourens van der Meij wrote:
Thanks for solving my previous problem. Next, I am looking at creating
procedures.
I somehow do not manage to use VPL variables in sparql queries:
CREATE PROCEDURE VAS_PROPERTY_LABEL (in _uri varchar) {
for (sparql select ?v1_lab where { _uri skos:prefLabel ?v1_lab})
do {
^^^^^
RETURN "v1_lab";
}
RETURN _uri;
}
Can I use VPL variables in sparql queries in procedures?
(I know how to include "sql"-variables using $: but that does not seem
to be working here)
Are there examples specific to sparql VPL mixing available somewhere?
Thanks,
Lourens
------------------------------------------------------------------------------
Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day
trial. Simplify your report design, integration and deployment - and focus on
what you do best, core application coding. Discover what's new with
Crystal Reports now. http://p.sf.net/sfu/bobj-july
_______________________________________________
Virtuoso-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/virtuoso-users
