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How to filter the simple Subject in a SPARQL Query

I guess I am stuck at the basics with SPARQL. Can someone help ?

I simply wnat to filter all subjects containing "Mountain" of an RDS database.

Prefix lgdr:<http://linkedgeodata.org/triplify/> Prefix lgdo:<http://linkedgeodata.org/ontology/> 
Select * where { 
?s ?p ?o . 
filter (contains(?s, "Mountain"))
} Limit 1000

The query leads to an error:

Virtuoso 22023 Error SL001: The SPARQL 1.1 function CONTAINS() needs a string value as first argument
Solution

  • You can get it to "work" using:

    Prefix lgdr:<http://linkedgeodata.org/triplify/> Prefix lgdo:<http://linkedgeodata.org/ontology/> 
Select * where { 
?s ?p ?o . 
filter (contains(str(?s), "Mountain"))
} Limit 1000

    Note the additional str in the query.

    However, that results in

    Virtuoso S1T00 Error SR171: Transaction timed out

    and I am not sure how to deal with that.

    But in principle in works: When you use 

    Limit 1

    you get

    s   p   o
http://linkedgeodata.org/ontology/MountainRescue    http://www.w3.org/1999/02/22-rdf-syntax-ns#type     http://www.w3.org/2002/07/owl#Class