User talk:Datumizer
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Best regards! Liuxinyu970226 (talk) 14:27, 26 May 2017 (UTC)
items without some properties
[edit]last time I forgot about nested optionals. I thought it is something intuitive, but it wasn't.
If you encounter similar questions, please ask them. Hopefully, code below is exactly what you want:
The following query uses these:
- Items: Bob's Game (Q4931588)
, 64 Hanafuda: Tenshi no Yakusoku (Q1107793)
- Properties: publication date (P577)
SELECT ?game ?date ?statementNodeType ?check0 ?check1 ?check2 ?check3 WHERE { VALUES ?game { wd:Q4931588 # no value wd:Q1107793 # one value wd:Q18857304 # unknown value wd:Q2385 # multiple values wd:Q23647080 # no property } OPTIONAL { ?game p:P577 ?statementNode OPTIONAL { ?statementNode ps:P577 ?date } OPTIONAL { ?statementNode rdf:type ?statementNodeType FILTER (?statementNodeType IN (wdno:P577)) } } BIND(IF(BOUND(?statementNode),true,false) as ?check0) # property is here? BIND(COALESCE(DATATYPE(?date) = xsd:dateTime , false) as ?check1) # real date? BIND(COALESCE((wdno:P577 = ?statementNodeType), false) as ?check2) # no value? BIND(COALESCE(isBlank(?date) , false) as ?check3) # unkown? }