Inception of RDF: Context

Transcription

1

2

3

4

5 Inception of RDF: Context Fukuoka City Homepage Gnavi page (Fukuoka) Municipal Documents (Fukuoka city) List of nursery in Fukuoka The www is a mine of information This is however mostly unstructured information Such www is useful to us human, because our brain is an outstanding information processor It is however not amenable to machines 5 www

6

7

8

9

10 Resource Description Framework

11

12

13

14

15

16

17

18

19

20

21

22 rdfs:type schema:website schema:about schema:lastreviewed rdfs:label db:fukuoka " "^^xsd:date rdfs:label "Fukuoka city official

23

24 Fukuoka City Homepage rdfs:type schema:website schema:about schema:lastreviewed rdfs:label db:fukuoka " "^^xsd:date rdfs:label "Fukuoka city official List of nurseries in Fukuoka rdfs:type schema:about schema:lastreviewed rdfs:label rdfs:label schema:website db:fukuoka " "^^xsd:date " List of nurseries in

25 rdfs:type schema:website schema:website schema:about schema:lastreviewed rdfs:label rdfs:label rdfs:type db:fukuoka schema:about schema:lastreviewed " "^^xsd:date rdfs:label rdfs:label "Fukuoka city official " List of nurseries in db:fukuoka " "^^xsd:date " List of nurseries in Both pages are about the same resource db:fukuoka db:fukuoka rdfs:label schema:about rdfs:label schema:lastreviewed rdfs:type " "^^xsd:date schema:about schema:lastreviewed rdfs:label rdfs:type schema:website rdfs:label "Fukuoka city official

26 " List of nurseries in rdfs:label schema:website rdfs:type rdfs:label schema:lastreviewed " "^^xsd:date rdfs:type schema:about rdfs:label "Fukuoka" schema:lastreviewed rdfs:label rdfs:label rdfs:label db:fukuoka schema:about rdfs:label geo:lat "Fukuoka city official geo:lon " "^^xsd:float "130.4"^^xsd:float These are data originated from dbpedia s database (includes longitude, latitude, and much more!!)...

27 This example is from lod-cloud.net

28

29 .rdf

30 .rdf

31 <p about= myself" vocab=" typeof="person"> My name is <span property="name">antoine Trouvé</span>, my phone number is <span property="telephone">xxx-xxxx-xxx</span> and my homepage is <a property="url" href=" </p> schema:name Antoine Trouvé myself schema:label schema:url xxx-xxxx-xxx

32

33 < < < < < < < < ^^< < < Fukuoka city official <

34 < < < < < < < < ^^< < < Fukuoka city official <

35 < < < < < < < < ^^< < < Fukuoka city official < prefix rdfs: << prefix schema: < prefix db: < prefix xsd: < < rdfs:type schema:website. < schema:about db:fukuoka. < schema:lastreviewed " "^^xsd:date. < rdfs:label "Fukuoka city official < rdfs:label

36 prefix rdfs: << prefix schema: < prefix db: < prefix xsd: < < rdfs:type schema:website ; schema:about db:fukuoka ; schema:lastreviewed " "^^xsd:date ; rdfs:label "Fukuoka city official homepage"@en ; rdfs:label ""@ja. prefix rdfs: << prefix schema: < prefix db: < prefix xsd: < < rdfs:type schema:website ; schema:about db:fukuoka ; schema:lastreviewed " "^^xsd:date ; rdfs:label "Fukuoka city official ""@ja.

37

38

39

40 !

41 Comparison RDF vs. Relational Relational Database RDF Query language SQL SPARQL Database technology Relational database Triple store (RDF store, graph store) Data model Relational Model RDF 1.1 Abstract Syntax 41

42 prefix db: < prefix rdfs: < SELECT?s WHERE {?s rdfs:label }

43 prefix db: < prefix rdfs: < SELECT?s WHERE {?s rdfs:label }

44 prefix db: < prefix rdfs: < SELECT?s WHERE {?s rdfs:label }

45

46 ?s ; geo:lon?longitude.

47

48 SELECT?name?lon?lat WHERE { GRAPH <graph IRI> {?s rdfs:label?name ; geo:lon?lon ; geo:lat?lat. } }

49 SELECT DISTINCT?g WHERE { } GRAPH?g {?s?p?o }

50 SELECT?name FROM <iri1> FROM NAMED <iri2> FROM NAMED <iri3> WHERE { {?s rdfs:label?name } UNION { GRAPH?g {?s rdfs:label?name } } } www

51 SELECT?name FROM <iri1> FROM NAMED <iri2> FROM NAMED <iri3> WHERE { {?s rdfs:label?name } UNION { GRAPH?g {?s rdfs:label?name } } } www

52 SELECT DISTINCT?name WHERE { SERVICE < {?s rdfs:label?name } } www

53 SELECT DISTINCT?name WHERE { SERVICE < {?s rdfs:label?name } } www

54

55

56

57 INSERT {?a foaf:friend?b ; foaf:knows?b.?b foaf:knows?a. } WHERE {?b foaf:friend?a }

58

59 About Vocabulary Depending on the data you hold, you may need various vocabulary You may create your own But someone may have done the job for you! There are some W3C standard vocabularies RDF and RDF Schema (RDFS) geo for geographical data (e.g. longitude / latitude) SKOS, the simple knowledge organization system XSD, data types from the XML standards And some other well-established vocabularies Foaf (Friend of a friend) to describe human relations Schema.org to casually describe misc. resources such as public facilities, websites or drugs (aimed at being a general purpose vocabulary for RDFa and Microdata) Dublin Core to describe bibliographical resources DBPedia, Yago, two general-purpose vocabularies, used for online encyclopedia 59

60 About Vocabulary Depending on the data you hold, you may need various vocabulary You may create your own But someone may have done the job for you! There are some W3C standard vocabularies RDF and RDF Schema (RDFS) geo for geographical data (e.g. longitude / latitude) SKOS, the simple knowledge organization system XSD, data types from the XML standards And some other well-established vocabularies Foaf (Friend of a friend) to describe human relations Schema.org to casually describe misc. resources such as public facilities, websites or drugs (aimed at being a general purpose vocabulary for RDFa and Microdata) Dublin Core to describe bibliographical resources DBPedia, Yago, two general-purpose vocabularies, used for online encyclopedia 60

61 Find a vocabulary on prefix.cc Example of RDFS Used to describe RDF schema (we ll see later) W3C recommandation prefix.cc shows us the ranking of most popular vocabularies 61

62 62

63 We get the turtle version of the vocabulary! 63

64 We get the turtle version of the vocabulary! 64

65

66

67

68

69

70

71

72

73

74

75 (nginx) Apache Fuseki SPARQL LOD Apache TDB MongoDB GeoJSON API HTTP API (node.js) SPARQL API API HTTP API

76 (nginx) Apache Fuseki SPARQL LOD Apache TDB MongoDB GeoJSON API HTTP API (node.js) SPARQL API API HTTP API

77

78