166 Large Scale and Big Data
?author foaf:name ?name
OPTIONAL {
?class2 rdfs:subClassOf foaf:Document.
?doc2 rdf:type ?class2.
?doc2 dcterms:issued ?yr2.
?doc2 dc:creator ?author2
FILTER (?author=?author2 && ?yr2 < ?yr)
} FILTER (!bound(?author2))
}
Note that in diagram d of Figure 5.5, we refer to 800 million RDF triples to be able to
compare executions with and without vertical partitioning and 1600 million triples
for comparison with the other queries.
Q3. Select All Articles with Property (a) swrc:pages (b) swrc:month
SELECT ?article
WHERE {
?article rdf:type bench:Article.
?article ?property ?value
(a) FILTER (?property = swrc:pages)
(b) FILTER (?property = swrc:month)
}
Q3. The execution of query Q3a and Q3b requires only one j ...