Sparql a simple knowledge query
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SPARQL is a standard query language for retrieving and manipulating data stored in RDF format. It consists of three parts: a query language, a result format, and an access protocol. The query language uses graph patterns to match against RDF graphs. It supports keywords like SELECT, FROM, and WHERE to identify values to return, data sources, and triple patterns to match. SPARQL can be run over HTTP or SOAP and returns XML results. It provides a unified method for querying RDF data distributed across the web.
Sparql a simple knowledge query
- 1. SPARQL : A Simple Knowledge Query STANLEY WANG SOLUTION ARCHITECT, TECH LEAD @SWANG68 http://www.linkedin.com/in/stanley-wang-a2b143b
- 2. Querying RDF data • RDF is a directed, labeled graph data format for representing the first layer information in semantic web standards; • Query patterns are like RDF triples except that each of the subject, predicate and object may be a variable; SPARQL • W3C standard recommendation in Q3 2007 • A query language based on graph patterns • Protocol layer for using SPARQL over HTTP • SPARQL endpoints on the Web • SPARQL used to construct graphs SPARQL stands for Protocol and RDF Query Language
- 3. 3 SPARQL as a Unifying Source SPARQL in 3 Parts 1. Query Language 2. Result Format 3. Access Protocol
- 4. SPARQL Query SELECT ... FROM ... WHERE { ... } SELECT clause to identify the values to be returned FROM clause to identify the data sources to query WHERE clause the triple/graph pattern to be matched against the triples/graphs of RDF a conjunction of triples: { ?x rdf:type ex:Person ?x ex:name ?name } PREFIX declare the schema used in the query
- 5. Example Persons and their Names 5 PREFIX ex: <http://inria.fr/schema#> SELECT ?person ?name WHERE { ?person rdf:type ex:Person ?person ex:name ?name . }
- 6. 6 <?xml version="1.0"?> <sparql xmlns="http://www.w3.org/2005/sparql-results#" > <head> <variable name="person"/> <variable name="name"/> </head> <results ordered="false" distinct="false"> <result> <binding name="person"> <uri>http://inria.fr/schema#fg</uri> </binding> <binding name="name"> <literal>gandon</literal> </binding> </result> <result> ...
- 7. with HTTP Binding GET /sparql/?query=<encoded query> HTTP/1.1 Host: www.inria.fr User-agent: my-sparql-client/0.1 SPARQL Protocol • Sending Queries and their Results Across the Web with SOAP Binding <?xml version="1.0" encoding="UTF-8"?> <soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <soapenv:Body> <query-request xmlns="http://www.w3.org/2005/09/sparql- protocol-types/#"> <query>SELECT ?x ?p ?y WHERE {?x ?p ?y}</query> </query-request> </soapenv:Body> </soapenv:Envelope>
- 8. • We need to associate a number of factors, including hospital type and facilities – its accessibility after a disaster – and the staff available • The query needs to be structured based on Concepts & Relationships that can be retrieved and then customized for the specific query. • Using this approach, a listing of the hospitals capable of dealing with large number of burn cases is returned to the user and information associated with the query retrieved. A “Simple” Knowledge Query Which hospitals within 30 mins of Alpine, CA provide burn treatment?”