Semantic Data

Chapter 7 : The semantic web query language

SPARQL

Jean-Louis Binot

1 18/03/2020Semantic Data

Sources

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Agenda

Querying RDF graphs1

SPARQL syntax and semantics2

Entailment regimes and OWL3

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What is SPARQL ?

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SPARQL engine

SPARQL queries

SPARQL updatesRDF dataset

RDF store

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Graph matching: basic idea

Dataset

Query pattern

Result

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Graph matching: basic idea

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Graph matching: basic idea ./.

Dataset

Query pattern

Result

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Graph matching: combining triples

DatasetQuery pattern

Result

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Graph matching: traversing a graph

DatasetQuery pattern

Result

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Agenda

Querying RDF graphs1

SPARQL syntax and semantics2

Entailment regimes and OWL3

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A full example

SPARQL QUERY ENDPOINT

http://librdf.org/query/

DATASET FILE (Turtle)

RDF/XML

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SPARQL basic query structure

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Graph patterns

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Examples

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Matching literals and blank nodes

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Query modifiers

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Query form DESCRIBE

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Aggregates

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Semantics of an answer to a graph pattern query

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Agenda

Querying RDF graphs1

SPARQL syntax and semantics2

Entailment regimes and OWL3

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Beyond RDF ?

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Reminder : RDF/RDFS entailment patterns

If S contains: then S RDF(S)_entails :

a p "v"^^d . a p _:b . _b rdf:type d .

a p b . p rdf:type rdf:Property .

any IRI a in D a rdf:type rdfs:Datatype .

p rdfs:domain x .

a p b .a rdf:type x .

p rdfs:range x .

a p b .b rdf:type x .

a p b . a rdf:type rdf:Resource .

a p b . b rdf:type rdf:Resource .

p rdfs:subPropertyOf q .

q rdfs:subPropertyOf r .p rdfs:subPropertyOf r .

a rdf:type rdf:Property . a rdfs:subPropertyOf a .

rdfs:subPropertyOf q .

a p b.a q b .

c rdf:type rdfs:Class . c rdfs:subClassOf rdf:Resource .

c rdfs:subClassOf d .

a rdf:type c.a rdf:type d .

c rdf:type rdfs:Class . c rdfs:subClassOf c .

c rdfs:subClassOf d .

d rdfs:subClassOf e .c rdfs:subClassOf e .

rdf:type rdfs:ContainerMembershipProperty . p rdfs:subPropertyOf rdfs:member .

d rdf:type rdfs:Datatype . d rdfs:subClassOf rdfs:Literal .

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Influence of entailment regime

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Querying OWL with SPARQL

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Summary

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References

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THANK YOU

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