|
|
| (43 intermediate revisions by 4 users not shown) |
| Line 1: |
Line 1: |
| == SPARQL Examples from Lecture 03==
| |
|
| |
|
| The data are available in this Blazegraph triple store:
| |
| [http://sandbox.i2s.uib.no] .
| |
|
| |
| ===List properties===
| |
|
| |
|
| |
| SELECT DISTINCT ?p WHERE {
| |
| ?s ?p ?o .
| |
| } LIMIT 100
| |
|
| |
|
| |
| ===List types===
| |
|
| |
| PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
| |
|
| |
| SELECT DISTINCT ?t WHERE {
| |
| ?s rdf:type ?t .
| |
| } LIMIT 100
| |
|
| |
| ===List authors===
| |
|
| |
| PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
| |
| PREFIX foaf: <http://xmlns.com/foaf/0.1/>
| |
|
| |
| SELECT DISTINCT ?p WHERE {
| |
| ?s rdf:type foaf:Person .
| |
| ?s ?p ?o .
| |
| } LIMIT 100
| |
|
| |
| ===Prefrixes used===
| |
|
| |
| The examples below will assume that these are in place.
| |
|
| |
| PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
| |
| PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
| |
| PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
| |
| PREFIX owl: <http://www.w3.org/2002/07/owl#>
| |
| PREFIX dc: <http://purl.org/dc/terms/>
| |
| PREFIX bibo: <http://purl.org/ontology/bibo/>
| |
| PREFIX foaf: <http://xmlns.com/foaf/0.1/>
| |
| PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
| |
| PREFIX ss: <http://semanticscholar.org/>
| |
| PREFIX kg: <http://i2s.uib.no/kg4news/>
| |
| PREFIX sp: <http://i2s.uib.no/kg4news/science-parse/>
| |
| PREFIX th: <http://i2s.uib.no/kg4news/theme/>
| |
|
| |
| SELECT DISTINCT ?p WHERE {
| |
| ?s rdf:type ss:Paper .
| |
| ?s ?p ?o .
| |
| } LIMIT 100
| |
|
| |
| ===Explain all types and properties===
| |
|
| |
| SELECT ?pt ?e WHERE {
| |
| ?pt rdfs:comment ?e .
| |
| } LIMIT 100
| |
|
| |
| ===List main papers===
| |
|
| |
| SELECT * WHERE {
| |
|
| |
| ?paper rdf:type kg:MainPaper .
| |
| ?paper dc:date ?year .
| |
|
| |
| }
| |
|
| |
| Add this to show datatypes!
| |
| BIND ( DATATYPE(?year) AS ?type )
| |
|
| |
| Add this to only show years with the right type.
| |
| FILTER ( DATATYPE(?year) = xsd:gYear )
| |
|
| |
| ===Group and count main papers by year===
| |
|
| |
| SELECT ?year (COUNT(?paper) AS ?count) WHERE {
| |
|
| |
| ?paper rdf:type kg:MainPaper .
| |
| ?paper dc:date ?year .
| |
| FILTER ( DATATYPE(?year) = xsd:gYear )
| |
|
| |
| }
| |
| GROUP BY ?year
| |
|
| |
| Add this to order the results
| |
| ORDER BY ?year
| |
|
| |
| Add this to order and only show years with more than 5 papers.
| |
| HAVING (?count > 5)
| |
| ORDER BY DESC(?count)
| |
|
| |
| ===Show papers
| |
|
| |
| SELECT ?paper ?year WHERE {
| |
|
| |
| ?paper rdf:type kg:MainPaper .
| |
| ?paper dc:date ?year .
| |
| FILTER ( DATATYPE(?year) = xsd:gYear )
| |
|
| |
| }
| |
|
| |
| Change last lines to show papers without an xsd:gYear too.
| |
| OPTIONAL {
| |
| ?paper dc:date ?year .
| |
| FILTER ( DATATYPE(?year) = xsd:gYear )
| |
| }
| |
|
| |
| *** VALUES
| |
|
| |
| SELECT ?p ?n ?year WHERE {
| |
| ?p rdf:type kg:MainPaper .
| |
| ?p dc:contributor ?a .
| |
| ?a foaf:name ?n .
| |
| ?p dc:date ?year .
| |
| FILTER ( CONTAINS( ?n, ?str ) )
| |
| FILTER ( CONTAINS( STR(?year), ?yr) )
| |
|
| |
| VALUES ?str { "Andreas" "David" }
| |
| VALUES ?yr { "2020" "2019" }
| |
| }
| |
|
| |
| *** PROPERTY PATH
| |
|
| |
| SELECT ?p ?n WHERE {
| |
| ?p rdf:type kg:MainPaper .
| |
| ?p dc:contributor / foaf:name ?n .
| |
| }
| |
|
| |
| SELECT ?p ?n WHERE {
| |
| kg:MainPaper ^rdf:type ?p .
| |
| ?p dc:contributor / foaf:name ?n .
| |
| }
| |
|
| |
| SELECT ?n WHERE {
| |
| kg:MainPaper ^rdf:type / dc:contributor / foaf:name ?n .
| |
| }
| |
|
| |
|
| |
| SELECT ?t WHERE {
| |
| ?t ^dc:title / dc:subject / skos:prefLabel "SPARQL" .
| |
| }
| |
|
| |
| SELECT ?t WHERE {
| |
| ?t ^dc:title / dc:subject / th:theme / skos:prefLabel "SPARQL" .
| |
| }
| |
|
| |
| SELECT ?t WHERE {
| |
| ?t ^dc:title / dc:subject / th:theme? / skos:prefLabel "SPARQL" .
| |
| }
| |
|
| |
| --
| |
|
| |
| SELECT ?a ?n ?r WHERE {
| |
| ?a rdf:type ss:Topic .
| |
| ?a skos:prefLabel ?n .
| |
| FILTER ( ?n = "SPARQL" )
| |
| BIND ( STRLANG( ?n, "en" ) AS ?n2 )
| |
| SERVICE <https://dbpedia.org/sparql> {
| |
| ?r rdfs:label ?n2 .
| |
| }
| |
| } LIMIT 1
| |
|
| |
| --
| |
|
| |
| SELECT * WHERE {
| |
|
| |
| ?p rdf:type kg:MainPaper .
| |
| ?p dc:date ?d .
| |
| FILTER ( DATATYPE(?d) = xsd:gYear )
| |
|
| |
| }
| |
|
| |
| --
| |
|
| |
| SELECT * WHERE {
| |
|
| |
| ?p rdf:type kg:MainPaper .
| |
| ?p dc:date ?d .
| |
| FILTER ( DATATYPE(?d) = xsd:dateTime )
| |
| BIND ( year( ?d ) AS ?dt )
| |
|
| |
| }
| |
