It would be a good idea to add default queries to the plugin.
This requires:
A query to find out some/all geospatial concepts of a triple store, sth. like this:
SELECT DISTINCT ?class WHERE{
?item wdt:P31 ?class.
?item wdt:P625 ?coord.}
Could be a performance issue though.
A query to select some/all direct properties of individuals of the class in a certain area as a default query.
Input: Concept (from previous query), boundingbox or concept like country, language
select ?rel ?relLabel WHERE {
?con wdt:P31 CONCEPT .
?con wdt:P625 ?coord .
?con wdt:P17 AREA . (or Boundingbox query part)
?con ?rel ?val .
SERVICE wikibase:label { bd:serviceParam wikibase:language LANGUAGE . } }
GROUP BY ?rel ?relLabel
ORDER BY ?relLabel
Ideally, a user could choose or search a list of geospatial concepts of the respective triple store and with the provision of boundingbox or country get a GeoJSON layer into QGIS.
This would increase the accessibility of the plugin to users who are not able to write SPARQL.
It would be a good idea to add default queries to the plugin. This requires:
A query to find out some/all geospatial concepts of a triple store, sth. like this: SELECT DISTINCT ?class WHERE{ ?item wdt:P31 ?class. ?item wdt:P625 ?coord.} Could be a performance issue though.
A query to select some/all direct properties of individuals of the class in a certain area as a default query. Input: Concept (from previous query), boundingbox or concept like country, language select ?rel ?relLabel WHERE { ?con wdt:P31 CONCEPT . ?con wdt:P625 ?coord . ?con wdt:P17 AREA . (or Boundingbox query part) ?con ?rel ?val . SERVICE wikibase:label { bd:serviceParam wikibase:language LANGUAGE . } } GROUP BY ?rel ?relLabel ORDER BY ?relLabel
Ideally, a user could choose or search a list of geospatial concepts of the respective triple store and with the provision of boundingbox or country get a GeoJSON layer into QGIS. This would increase the accessibility of the plugin to users who are not able to write SPARQL.