SPARQL/字首
外觀
< SPARQL
WDQS 理解許多快捷縮寫,稱為字首。一些是 Wikidata 內部使用的,如 wd、wdt、p、ps、bd 等,還有許多其他常用的外部字首,如 rdf、skos、owl、schema 等。
在下面的查詢中,我們正在查詢存在 "P279 = Q7725634" 語句的專案,或者更準確地說,選擇具有 "子類" 屬性和 "文學作品" 物件的主體。
對於簡單的 WDQS 三元組,專案應該以 wd: 為字首,屬性應該以 wdt: 為字首。這僅適用於固定值 - 變數沒有字首。
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").
}
}
不使用字首,應該寫成
# 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").
}
}
實際上,所有提到的字首都在 Wikidata 查詢服務中內建,因此可以省略它們。
# 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").
}
}
內建字首的完整列表是
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#>