Hi all,

after a tweet from Magnus [0] we talked a bit about entries without
statements (about 2.5M) and on the question if SPARQL could list all
entries in Wikidata that do not have statements. I played a bit with
combinations of OPTIONAL and FILTER-BOUND and FILTER NOT EXIST...
something like:

PREFIX wikibase: <http://wikiba.se/ontology#>
SELECT DISTINCT ?entry ?label ?statement WHERE {
  ?entry rdfs:label ?label . FILTER (lang(?label) = "en")
  FILTER NOT EXISTS {
    ?statement ?prop ?entry ;
      wikibase:rank ?rank .
  }
} LIMIT 5

These queries tend to fail. Now, I'm not at all a SPARQL wizard and
maybe there is a simple way to not run into the time outs that I do
now.

But there was something else I noted... statements are not typed...
that would probably kick in some index, rather than the above query,
and the documentation actually speaks about wikibase:Statement [1] but
if I search for anything rdf:type-d as such, then it finds nothing in
the SPARQL end point:

https://query.wikidata.org/#PREFIX%20wikibase%3A%20%3Chttp%3A%2F%2Fwikiba.se%2Fontology%23%3E%0Aselect%20%3Fstat%20where%20%7B%0A%20%20%3Fstat%20%3Fpred%20wikibase%3AStatement%0A%7D%20limit%205

Did this typing get lost at some point or is the documentation outdated?

Greetings,

Egon

0.https://twitter.com/MagnusManske/status/685499058228715520
1.https://www.mediawiki.org/wiki/Wikibase/Indexing/RDF_Dump_Format#Statement_types

-- 
E.L. Willighagen
Department of Bioinformatics - BiGCaT
Maastricht University (http://www.bigcat.unimaas.nl/)
Homepage: http://egonw.github.com/
LinkedIn: http://se.linkedin.com/in/egonw
Blog: http://chem-bla-ics.blogspot.com/
PubList: http://www.citeulike.org/user/egonw/tag/papers
ORCID: 0000-0001-7542-0286
ImpactStory: https://impactstory.org/EgonWillighagen

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