The W3C officially unveiled the SPARQL Query Language today via
a press release titled: W3C Opens Data on the Web with SPARQL.
A query language for the burgeoning Structured & Linked Data Web (aka Semantic Web / Giant Global Graph). Like SQL, for
the Relational Data Model, it provides a query language for the
Graph based RDF Data Model.
It's also a REST or SOAP
based Web Service that exposes SPARQL access to RDF Data via an
endpoint.
In addition, it's also a Query Results Serialization format that
includes XML and JSON
support.
Why is it Important?
It brings important clarity to the notion of the "Web as a
Database" by transforming existing Web Sites, Portals, and Web
Services into bona fide corpus of Mesh-able (rather than Mash-able)
Data Sources. For instance, you can perform queries that join one
or more of the aforementioned data sources in exactly the same
manner (albeit different syntax) as you would one or more SQL
Tables.
Example:
-- SPARQL equivalent of SQL SELECT * against my personal data
space hosted FOAF file
SELECT DISTINCT ?s ?p ?o
FROM <http://myopenlink.net/dataspace/person/kidehen>
WHERE {?s ?p ?o}
-- SPARQL against my social network -- Note: My SPARQL will be
beamed across all of contacts in the social networks of my contacts
as long as they are all HTTP URI based within each data space
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
SELECT DISTINCT ?Person
FROM <http://myopenlink.net/dataspace/person/kidehen>
WHERE {?s a foaf:Person; foaf:knows ?Person}
Note: you can use the basic SPARQL
Endpoint, SPARQL Query By Example, or SPARQL Query Builder Demo tool to experiment
with the demonstration queries above.
How Do I use It?
SPARQL is implemented by RDF Data Management Systems (Triple or
Quad Stores) just as SQL is implemented by Relational Database
Management Systems. The aforementioned data management systems will
typically expose SPARQL access via a SPARQL endpoint.
Where are it's implementations?
A SPARQL implementors Testimonial page accompanies the SPARQL
press release. In addition the is a growing collection of
implementations on the ESW Wiki Page for SPARQL compliant RDF Triple
& Quad Stores.
Is this really a big deal?
Yes! SPARQL facilitates an unobtrusive manifestation of a Linked Data
Web by way of natural extension of the existing Document Web
i.e these Web enclaves co-exist in symbiotic fashion.
As DBpedia
very clearly demonstrates, Linked Data makes the Semantic Web
demonstrable and much easier to comprehend. Without SPARQL there
would be no mechanism for Linked Data deployment, and without Linked
Data there is no mechanism for Beaming Queries (directly or
indirectly) across the Giant Global Graph of data hosted by Social
Networks, Shard Bookmarks Services, Weblogs, Wikis, RSS/Atom/OPML
feeds, Photo Galleries and other Web accessible Data Sources (Data
Spaces).
Related items
Detailed
SPARQL Query Examples using SIOC Data Spaces