Talk:Wikidata query service/User Manual

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Item count[edit]

How can I just count the number of items that match a certain query? I mean, I get the total with the result set, but if the total is very large, the browser tab explodes, and loading the entire dataset is unnecessary anyway, since all I want is the number.

I tried to use SPARQL's COUNT() but got a syntax error. grepping the User Manual for 'count' returned no results either. I'm guessing this is a FAQ, so perhaps an answer should be added to the manual, even if it is "currently you can't". Ijon (talk) 22:01, 30 October 2015 (UTC)

This is standard SPARQL. Try something like: SELECT (COUNT(DISTINCT ?x) AS ?count) WHERE { ... } Cheers, Bovlb (talk) 01:59, 17 October 2016 (UTC)

ranks[edit]

Is there a way to take ranks into account, like ignoring deprecated statements in d:Wikidata:Database reports/items with P569 greater than P570. --Zolo (talk) 08:16, 27 January 2016 (UTC)

Sitelinks[edit]

The manual is still missing how to get sitelinks. And is it possible to get only the sitelinks of a certain namespace? --Tobias1984 (talk) 13:05, 27 May 2016 (UTC)

I remember writing such a query and posting it to the #wikidata IRC channel, but I couldn't easily recreate it. The problem is that the contains function does not directly work on the URLs. Currently I'm a bit too swamped to search in the logs. -- Jan Zerebecki 14:30, 1 June 2016 (UTC)
Querying for sitelinks is described here: https://www.wikidata.org/wiki/Wikidata:SPARQL_query_service/queries#Working_with_sitelinks Bovlb (talk) 02:12, 17 October 2016 (UTC)

Translations[edit]

Hi

Thank you for this amazing tool!

In order to make it easier to use, have you considered to mark that manual for translation?

Thanks, Trizek (talk) 13:29, 18 June 2016 (UTC)

@Trizek: Since no one has replied to this section in six months and a few changes have been made to the page, I think there should be no problem. If is it, anyone could cancel and we can discuss.
Ogoorcs (talk) 21:30, 5 March 2017 (UTC)

Invalid example[edit]

The example "showing the list of US presidents and their spouses" (section "Label service") results in the following error (when trying to evaluate it following the link "Try it"):

Query is malformed: QName 'v:P6' uses an undefined prefix

The prefix "v" is not defined in the menu "Prefixes" in the query tool, and I cannot find it in this page either.

--FGeorges (talk) 05:49, 6 October 2016 (UTC)

I have fixed it. It should have been ps: . Bovlb (talk) 02:10, 17 October 2016 (UTC)
Just tried it, works for me indeed. Thanks!
--FGeorges (talk) 16:54, 21 October 2016 (UTC)

Map view, multiple columns[edit]

For the map view, when there are multiple co-ordinate columns, it would be good to display them in distinct colors. Example query - http: //tiny url.com/h35p92u Bovlb (talk) 01:57, 17 October 2016 (UTC)

@Bovlb: plese just use full urls, not shorteners. url shorteners are blacklisted for a reason.

Label_service returns IllegalArgumentException[edit]

@Smalyshev (WMF):: Wikidata_query_service/User_Manual#Label_service can be more robust. This query

select ?x ?Label where {
  ?x wdt:P31 wd:Q328468.
  SERVICE wikibase:label {bd:serviceParam wikibase:language "en,de,pl"}
}

returns "Unknown error: java.lang.IllegalArgumentException".

The reason is there's nothing between "?" and "Label" in the second var. (It's looking for "x" or "xAlt") --Vladimir Alexiev (talk) 19:59, 13 March 2017 (UTC)