query-11d3e664810e8b4fe629f2f1ccc208c5
Retrieve property if availableWithin the following query I want to extract the P580 (start time) property of a statement "heritage designation" (wdt:P1435) is "World Heritage Site" (wd:Q9259) if that property is available and display as ?st. How can I extend the statement within the OPTIONAL clause to accomplish this? As an example: in Q1620833 the start time would be 2002.
Use at
- https://query.wikidata.org/sparql
PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX bd: <http://www.bigdata.com/rdf#>
SELECT ?item ?whsId ?st WHERE {
?item wdt:P757 ?whsId.
OPTIONAL {
?item wdt:P1435 wd:Q9259
}
SERVICE wikibase:label { bd:serviceParam wikibase:language "en". }
}
Query found at
graph TD
classDef projected fill:lightgreen;
classDef literal fill:orange;
classDef iri fill:yellow;
v1("?item"):::projected
v2("?whsId"):::projected
c5(["bd:serviceParam"]):::iri
c7(["en"]):::literal
c3(["wd:Q9259"]):::iri
v1 --"wdt:P757"--> v2
subgraph optional0["(optional)"]
style optional0 fill:#bbf,stroke-dasharray: 5 5;
v1 -."wdt:P1435".-> c3
end
subgraph s1["http://wikiba.se/ontology#label"]
style s1 stroke-width:4px;
c5 --"wikibase:language"--> c7
end