SPARQL/Prefixes

WDQS understands many shortcut abbreviations, known as prefixes. Some are internal to Wikidata wd, wdt, p, ps, bd, etc. and many others are commonly used external prefixes, like rdf, skos, owl, schema, etc.

In the following query, we are asking for items where there is a statement of "P279 = Q7725634" or in fuller terms, selecting subjects that have a predicate of "subclass of" with an object of = "literary work".

For simple WDQS triples, items should be prefixed with wd:, and properties with wdt:. This only applies to fixed values – variables don’t get a prefix.

PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wds: <http://www.wikidata.org/entity/statement/>
PREFIX wdv: <http://www.wikidata.org/value/>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX p: <http://www.wikidata.org/prop/>
PREFIX ps: <http://www.wikidata.org/prop/statement/>
PREFIX pq: <http://www.wikidata.org/prop/qualifier/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX bd: <http://www.bigdata.com/rdf#>

# The below SELECT query does the following:
# Selects all the items(?s subjects) and their descriptions(?desc)
# that have(WHERE) the statement(?s subject) has a direct property(wdt:) = P279 <subclasses of>
# with a value of entity(wd:) = Q7725634 <Literary Work>
# and Optionally return the label and description using the Wikidata label service

SELECT ?s ?desc WHERE {
  ?s wdt:P279 wd:Q7725634 .
  OPTIONAL {
      ?s rdfs:label ?desc 
      FILTER (LANG(?desc) = "en").
  }
}

Try it!

Without the use of prefixes this should be written as

# The below SELECT query does the following:
# Selects all the items(?s subjects) and their descriptions(?desc)
# that have(WHERE) the statement(?s subject) has a direct property(wdt:) = P279 <subclasses of>
# with a value of entity(wd:) = Q7725634 <Literary Work>
# and Optionally return the label and description using the Wikidata label service

SELECT ?s ?desc WHERE {
  ?s <http://www.wikidata.org/prop/direct/P279> <http://www.wikidata.org/entity/Q7725634> .
  OPTIONAL {
     ?s <http://www.w3.org/2000/01/rdf-schema#label> ?desc 
     FILTER (LANG(?desc) = "en").
  }
}

Try it!

Actually all mentioned prefixes are built in in the Wikidata Query Service, so they can be left out

# The below SELECT query does the following:
# Selects all the items(?s subjects) and their descriptions(?desc)
# that have(WHERE) the statement(?s subject) has a direct property(wdt:) = P279 <subclasses of>
# with a value of entity(wd:) = Q7725634 <Literary Work>
# and Optionally return the label and description using the Wikidata label service

SELECT ?s ?desc WHERE {
  ?s wdt:P279 wd:Q7725634 .
  OPTIONAL {
     ?s rdfs:label ?desc 
     FILTER (LANG(?desc) = "en").
  }
}

Try it!

The full list of built in prefixes is

PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wds: <http://www.wikidata.org/entity/statement/>
PREFIX wdv: <http://www.wikidata.org/value/>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX p: <http://www.wikidata.org/prop/>
PREFIX ps: <http://www.wikidata.org/prop/statement/>
PREFIX pq: <http://www.wikidata.org/prop/qualifier/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX bd: <http://www.bigdata.com/rdf#>

PREFIX wdref: <http://www.wikidata.org/reference/>
PREFIX psv: <http://www.wikidata.org/prop/statement/value/>
PREFIX psn: <http://www.wikidata.org/prop/statement/value-normalized/>
PREFIX pqv: <http://www.wikidata.org/prop/qualifier/value/>
PREFIX pqn: <http://www.wikidata.org/prop/qualifier/value-normalized/>
PREFIX pr: <http://www.wikidata.org/prop/reference/>
PREFIX prv: <http://www.wikidata.org/prop/reference/value/>
PREFIX prn: <http://www.wikidata.org/prop/reference/value-normalized/>
PREFIX wdno: <http://www.wikidata.org/prop/novalue/>
PREFIX wdata: <http://www.wikidata.org/wiki/Special:EntityData/>

PREFIX schema: <http://schema.org/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX prov: <http://www.w3.org/ns/prov#>
PREFIX bds: <http://www.bigdata.com/rdf/search#>
PREFIX gas: <http://www.bigdata.com/rdf/gas#>
PREFIX hint: <http://www.bigdata.com/queryHints#>

References

• mw:Wikibase/Indexing/RDF_Dump_Format#Prefixes_used - details about each prefix
• Wikidata query service/User Manual