Hi all.
I am Fernando.
I followed and I have collaborated in implementing geosparql since its beginnig.

Marmotta is our LD platform in some projects in University of Cuenca
But I have analyzed a situation that can be a problem regarding geosparql.

Using this file( 
https://wiki.apache.org/marmotta/MARMOTTA-584/UserDocumentation?action=AttachFile&do=view&target=provinciasEspa%C3%B1a.rdf
 ) 
At this time, marmotta answers the following query to get the WKT of the 
Province of Lleida

"PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>PREFIX geoes: 
<http://geo.marmotta.es/ontology#>PREFIX geo: 
<http://www.opengis.net/ont/geosparql#>
SELECT DISTINCT ?province ?wkt WHERE {  ?province a 
<http://geo.marmotta.es/ontology#provincia>.  ?province rdfs:label "Lleida"@es. 
 ?province geoes:hasExactGeometry ?geo.  ?geo geo:asWKT ?wkt.  }
"
But according to GeoSPARQL Standard,  marmotta should also answer the following 
query
"PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>PREFIX geo: 
<http://www.opengis.net/ont/geosparql#>
SELECT DISTINCT ?province ?wkt WHERE {  ?province a 
<http://geo.marmotta.es/ontology#provincia>.  ?province rdfs:label "Lleida"@es. 
 ?province geo:hasGeometry ?geo.  ?geo geo:asWKT ?wkt.  }
"
To retrieve the geographical resource, you need to use "geo:hasGeometry" 
instead of  "geoes:hasExactGeometry"

In the GeoSPARQL Standard Document  
[http://www.opengeospatial.org/standards/geosparql] mentioned the following
"Implementations shall allow the properties geo:hasGeometry 
andgeo:hasDefaultGeometry to be used in SPARQL graph patterns."



In the RDF,  exists the following relation
http://geo.marmotta.es/ontology#hasExactGeometry  is subPropertyOf  
http://www.opengis.net/ont/geosparql#hasGeometry
Then marmotta should infer this relation.


To solve this problem. I implement the following rule in the reasoner Module.
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>
($1 <http://www.w3.org/2000/01/rdf-schema#subPropertyOf> $2), ($3 $1 $4) -> ($3 
$2 $4)

Then my question is:
Is this process right for all geosparql users?
Is there other way for marmotta to infer this relation?







                                          

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