Querying the British National Bibliography

Following up on the earlier announcement that the British
Library has made the British National Bibliography available
under a public domain dedication, the JISC Open Bibliography
project has worked to make this data more useable.

The data has been loaded into a Virtuoso store that is queriable
through the SPARQL Endpoint and the URIs that we have assigned each
record use the ORDF software to make them dereferencable,
supporting perform content auto-negotiation as well as embedding RDFa
in the HTML representation.

The data contains some 3 million individual records and some 173
million triples. Indexing the data was a very CPU intensive process
taking approximately three days. Transforming and loading the source
data took about five hours.

To get an idea of the shape of the data, let us consider a sample
resource, http://bnb.bibliographica.org/entry/GB8102507 . Apart from
linkage between the various representations, the description of the
entity itself is as follows

@prefix ov: <http://open.vocab.org/terms/> .
@prefix isbd: <http://iflastandards.info/ns/isbd/elements/> .
@prefix bibo: <http://purl.org/ontology/bibo/> .
@prefix bio: <http://purl.org/vocab/bio/0.1/> .
@prefix dc: <http://purl.org/dc/terms/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<http://bnb.bibliographica.org/entry/GB8102507> a bibo:Book, bibo:Document;
  dc:source <http://bnb.bibliographica.org/dataset/BNBrdfdc03.xml#183143>;
  dc:isPartOf <http://bnb.bibliographica.org/dataset>;
  rdfs:seeAlso <http://purl.org/NET/book/isbn/0241105161#book>,
               <http://www4.wiwiss.fu-berlin.de/bookmashup/books/0241105161>;

  dc:title "A good man in Africa";
  dc:language [ rdf:value "eng"^^dc:ISO639-2 ];
  dc:extent [ rdfs:label "251p" ];

  dc:contributor [ a foaf:Agent;
                   foaf:name "Boyd, William";
                   skos:notation "Boyd, William, 1952-";
                   bio:event [ a bio:Birth;
                               bio:date "1952"^^xsd:gYear ];
                   = <http://bibliographica.org/entity/735b02a8f051e2249e40fbd48112d033>;
                 ];

  dc:subject [ rdfs:label "Fiction in English" ],
             [ rdfs:label "1945-" ],
             [ rdfs:label "Texts" ],
             [ a skos:Concept;
               skos:inScheme <http://dewey.info/scheme/e18>;
               skos:notation "823/.9/1"^^<ddc:Notation> ],
             [ a skos:Concept;
               skos:inScheme <http://dewey.info/scheme/e19>;
               skos:notation "823/.914"^^<ddc:Notation> ].

  dc:publisher [ a foaf:Agent;
                 foaf:name "Hamilton";
                 skos:notation "Hamilton";
                 = <http://bibliographica.org/entity/c080da5b03a0786efa61e61123b359d9>;
               ];
  dc:issued "1981"^^xsd:gYear;
  isbd:hasPlaceOfPublicationProductionDistribution [ rdfs:label "London" ].

  bibo:identifier "GB8102507";
  bibo:isbn <urn:isbn:0241105161>;
  ov:blid "008042853".

Some of the salient features of this representation are:

• Assignment of URIs for each entry in the British National
  Bibliography under http://bnb.bibliographica.org/.
• Linkage with rdfs:seeAlso to the RDF Book Mashup and RDF
  Book Vocabulary.
• Author and publisher are preserved as blank nodes as in the source
  data but are augmented with owl:sameAs links into the
  Bibliographica namespace to support further annotation,
  correction, deduplication, etc.
• Any series if present is promoted to a first-class entity in the
  Bibliographica namespace for further processing.
• Extraction of birth and death dates from the canonical
  string representation for authors.
• For authors, publishers and series, their name as present in the
  source data is preserved using skos:notation whilst their
  names less any metadata about birth and death are represented with
  foaf:name.

The entire dataset is queriable through the SPARQL Endpoint and
makes use of some of the extended features of Virtuoso such as
full-text indexing. This is accomplished by using the bif:contains
built-in function and is what powers the search functionality on the
website. The default (example) query returns some details about all
books that have "Edinburgh" in their titles:

PREFIX dc: <http://purl.org/dc/terms/>
PREFIX bibo: <http://purl.org/ontology/bibo/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
SELECT DISTINCT ?book ?title ?name ?description
WHERE {
    ?book a bibo:Book .
    ?book dc:title ?title . ?title bif:contains "Edinburgh" .
    OPTIONAL { ?book dc:description ?description } .
    OPTIONAL {
        ?book dc:contributor ?author . ?author foaf:name ?name
    }
} GROUP BY ?book LIMIT 50

It should be noted that only some predicates are indexed for full-text
searching, namely,

• rdf:value
• rdfs:label
• rdfs:comment
• skos:prefLabel
• skos:altLabel
• dc:title
• dc:description
• foaf:name