NAME¶
librasqal - Rasqal RDF query library
SYNOPSIS¶
#include <rasqal.h>
rasqal_world*world=rasqal_new_world();
rasqal_query_results *results;
raptor_uri *base_uri=raptor_new_uri("http://example.org/foo");
rasqal_query *rq=rasqal_new_query(world,"rdql",NULL);
const char *query_string="select * from <http://example.org/data.rdf>";
rasqal_query_prepare(rq,query_string,base_uri);
results=rasqal_query_execute(rq);
while(!rasqal_query_results_finished(results)) {
for(i=0;i<rasqal_query_results_get_bindings_count(results);i++) {
const char *name=rasqal_query_results_get_binding_name(results,i);
rasqal_literal *value=rasqal_query_results_get_binding_value(results,i);
/* ... */
}
rasqal_query_results_next(results);
}
rasqal_free_query_results(results);
rasqal_free_query(rq);
raptor_free_uri(base_uri);
rasqal_free_world(world);
cc prog.c -o prog `pkg-config rasqal --cflags` `pkg-config rasqal --libs`
DESCRIPTION¶
The
Rasqal library provides a high-level interface to RDF query parsing,
query construction, query execution over an RDF graph and query results
manipulation and formatting. The library provides APIs to each of the steps in
the process and provides support for handling multiple query language
syntaxes. At present Rasqal supports most of the W3C SPARQL 1.0 Query
language, some of SPARQL 1.1 draft and fully supports RDQL.
Rasqal uses the
libraptor(3) library for providing URI handling, WWW content
retrieval and other support functions.
API REFERENCE¶
See the HTML API docs that may be installed system wide at
/usr/share/gtk-doc/html/rasqal/ or on the web at
http://librdf.org/rasqal/docs/api/
API CHANGES¶
See the Raptor API docs changes section at
http://librdf.org/rasqal/docs/api/rasqal-changes.html
SPARQL Query Language for RDF, Eric Prud'hommeaux and Andy Seaborne
(eds), W3C Recommendation, 15 January 2008
http://www.w3.org/TR/2008/REC-rdf-sparql-query-20080115/
SPARQL Query Results XML Format, Jeen Broekstra and Dave Beckett (eds),
W3C Recommendation, 15 January 2008.
http://www.w3.org/TR/2008/REC-rdf-sparql-XMLres-20080115/
RDQL - A Query Language for RDF, Andy Seaborne, W3C Member Submission 9
January 2004
http://www.w3.org/Submission/2004/SUBM-RDQL-20040109/
SEE ALSO¶
roqet(1),
libraptor(3)
AUTHOR¶
Dave Beckett -
http://purl.org/net/dajobe/