问题
I'm trying out the wikidata API but have some trouble with the search query "Jas 39 C Gripen". It returns results on the wikidata website, but not if I use the API.
On The wikidata website I get two search results for the query
https://www.wikidata.org/w/index.php?search=Jas+39+C+Gripen&title=Special:Search&fulltext=1
The same query using the API, does not return a result
https://www.wikidata.org/w/api.php?action=wbsearchentities&format=json&language=en&type=item&continue=0&search=Jas%2039%20C%20Gripen
Am I missing some parameters or using the wrong parameters? For many other queries I get results from the API.
回答1:
It seems that the native Wikidata search applies some "fuzzy logic" when interpreting the user's entries. In your case, it shows two results, although the character C is missing in the first one.
Coming back to the API and the action you have chosen, you could use Jas 39 Gripen as search term (which will show one result) as well as Jas 39C Gripen (which will also show one result). But it seems that you can't use Jas 39 C Gripen (note the space character between 9 and C).
In other words,
https://www.wikidata.org/w/api.php?action=wbsearchentities&format=json&language=en&type=item&continue=0&search=Jas%2039%20Gripen
https://www.wikidata.org/w/api.php?action=wbsearchentities&format=json&language=en&type=item&continue=0&search=Jas%2039C%20Gripen
both work, but
https://www.wikidata.org/w/api.php?action=wbsearchentities&format=json&language=en&type=item&continue=0&search=Jas%2039%20C%20Gripen
does not.
I have investigated this issue further and finally found the solution. Try this:
https://www.wikidata.org/w/api.php?action=query&list=search&format=json&srsearch=Jas+39+C+Gripen
The action query allows some "fuzziness" in the search term. Please refer to the API documentation for further details. In short, this action performs a full text search (which you obviously want) and allows for a nearmatch search type.
回答2:
The reason seems to be that the English label is JAS 39C Gripen. By removing one space from your query, you will get the result you are looking for:
https://www.wikidata.org/w/api.php?action=wbsearchentities&format=json&language=en&type=item&continue=0&search=Jas%2039C%20Gripen
来源：https://stackoverflow.com/questions/51949112/getting-search-results-from-wikidata-website-but-not-api