Problem with simple query

[Mikael Pesonen]

Hi,
im matching strings in different graphs and this should do the trick:

SELECT ?prefLabel ?s2
WHERE {
  GRAPH <http://www.lingsoft.fi/somegraph>
  {
    ?s skos:prefLabel ?prefLabel .
  }
  OPTIONAL {
    GRAPH ?graph
    {
      ?s2 skos:prefLabel ?label2

      FILTER ( lcase(str(?prefLabel)) = lcase(str(?label2)) )
    }
  }
}

but im not getting any results. There are plenty of matches in store and 
this returns them (case sensitive match)

SELECT ?prefLabel ?s2
WHERE {
  GRAPH <http://www.lingsoft.fi/somegraph>
  {
    ?s skos:prefLabel ?prefLabel .
  }
  OPTIONAL {
    GRAPH ?graph
    {
      ?s2 skos:prefLabel ?prefLabel
    }
  }
}


Im I using FILTER wrong way or could it be a bug in search engine?

Br,
Mikael

--
www.lingsoft.fi

Speech Applications - Language Management - Translation - Reader's and Writer's 
Tools - Text Tools - E-books and M-books

Mikael Pesonen
System Engineer

e-mail: mikael.peso...@lingsoft.fi
Tel. +358 2 279 3300

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