%META:TOPICPARENT{name="VirtTipsAndTricksGuide"}%

---++How Can I Perform Case Insensitive Search across multiple Literal values with Virtuoso?

If you use  <b>contains</b>, it will make an approximate filtering of results, its is therefore best to use <b>FILTER</b> with <b>bif:lower</b>. 

For example with the following RDF triples loaded in Virtuoso:
<verbatim>
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"An?lisis" .
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"Aut?nomas" .
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"Autonom?a de gobierno" .
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"Autonom?a" .
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"Auton?mica" .
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"Com?n" .
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"Comunidades" .
<http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D><http://rdfs.org/sioc/types#Tag>"Cr?tico" .
</verbatim>

The following query is case sensitive, thus no data is returned as is expected:
<verbatim>
SQL> SPARQL
PREFIX sioc_t:<http://rdfs.org/sioc/types#>
SELECT DISTINCT ?s
FROM <http://j.com>
WHERE 
  { 
    ?s sioc_t:Tag ?Tag.  FILTER ( ?Tag in ('analisi', 'autonomas', 
                                           'autonomia de gobierno', 
                                           'autonomia', 'autonomica', 
                                           'comun', 'comunidades', 'critico' ) )
  }

-- Query result:
s
ANY
No. of rows in result: 0 
</verbatim>

Changing the query to use the Virtuoso <b>bif:lower</b> function a case insensitive filter is performed returning one distinct row:

<verbatim>
SQL>SPARQL 
PREFIX sioc_t:<http://rdfs.org/sioc/types#>
SELECT DISTINCT ?s
FROM <http://j.com>
WHERE 
  { 
    ?s sioc_t:Tag ?Tag.  FILTER ( bif:lower(str(?Tag)) in ('analisi', 'autonomas', 
                                                           'autonomia de gobierno', 
                                                           'autonomia', 'autonomica', 
                                                           'comun', 'comunidades', 'critico' ) )
  }

-- Query result:
s
ANY
 http://gnoss/000066A5-E5C4-4317-AC9F-4A226E65AE4D
No. of rows in result: 1 
</verbatim>

---+++Related
   
   * [[VirtTipsAndTricksGuide][Virtuoso Tips and Tricks Collection]]
   * [[http://docs.openlinksw.com/virtuoso/sparqlextensions.html#rdfsparqlrulefulltext][Using Full Text Search in SPARQL]]