# filename: ex211.rq

PREFIX sch: <http://purl.org/net/schemarama#>
PREFIX dm:  <http://learningsparql.com/ns/demo#> 
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

CONSTRUCT
{
  [] rdf:type sch:Error;
        sch:message "location value should be a URI";
        sch:implicated ?s.

} 
WHERE
{
  ?s dm:location ?city .
  FILTER (!(isURI(?city)))
}