Wittylama

• one SPARQL tutorial
• a different SPARQL tutorial
• too many example queries
• Ijon's example queries from Tallinn
• the official too much information

Examples via Harmonia Amanda:

• • requesting qualifiers
  • requesting references
  • requesting NoValue

• Mandatory incantation before end of WHERE block

SERVICE wikibase:label {bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" }

• Property or any of its subclasses:

wdt:P31/wdt:P279*

• SELECT DISTINCT to return unique results (useful for when using "property or subclasses of" (wdt:P31/wdt:P279*)
•  To find whether an item has an article in Wikipedia, add:

  ?article schema:about ?item ;
           schema:isPartOf <https://en.wikipedia.org/>.

• ORDER BY goes inside brackets, GROUP BY does not. GROUP BY must list all the things not in special brackets (e.g. (COUNT(?sitelink) AS ?count)) in the SELECT line.

GROUP BY ?item ?itemLabel ?article
ORDER BY DESC(?count)
LIMIT 50

• To request NOT or EXCEPT something use MINUS { <the triple(s)> }.
• To request the number of pages in all wikimedia projects add ?sitelink schema:about ?item . as a triple, and (COUNT(?sitelink) AS ?count) in the SELECT block.
• OR statements are expressed with UNION between two sets of triples each within braces. e.g.

  { ?item wdt:P19 wd:Q13972 .} UNION {?item wdt:P19 wd:Q1770 .}
  

Articles:

• "All instances of <topic> that have an article on <language> Wikipedia". solution!
  • "...and also <different> language solution!
  • "...but not <different> language. solution!
  • ...sorted by number of total articles. solution!

Labels:

• "All instances of <topic> that have a <language> label"
  • "...and also <different> language
  • "...but not <different> language

• List of capitals (with country, foundation date, flag) of the EU gives three pairs of separate kinds of duplicates
• Asking for instances of and/or subclasses of "christmas decoration" gives different results for different ccombinations.
• Current physical libraries without geolocation. But two West German libraries still appear in the results.

Hi Wittylama - you have added yourself to the list of people who are interested in the WikiCite Satellite Cologne 2020 meeting. The call for submissions is still open and we would love to see your contribution! Let me know if you have any questions. Best wishes!

Konrad Foerstner (talk) 18:32, 12 February 2020 (UTC)