The normalization of UNICODE3 accented chars in free-text index can be controlled by setting up the configuration parameter XAnyNormalization in the virtuoso.ini config file, section [I18N]. This parameter controls whether accented UNICODE characters should be converted to their non-accented base variants at the very beginning of free-text indexing or parsing a free-text query string. The parameter's value is an integer that is bitmask with only 2 bits in use atm:

If the parameter is required at all, the needed value is probably 3. So the fragment of virtuoso.ini is:

[I18N]
XAnyNormalization=3

In some seldom case the value of 1 can be appropriate. The parameter should be set once before creating the database. If changed on the existing database, all free-text indexes that may contain non-ASCII data should be re-created. On a typical system, the parameter affects all text columns, XML columns, RDF literals and queries.

Strictly speaking, it affects not all of them but only items that use default "x-any" language or language derived from x-any such as "en" and "en-US" but if you haven't tried writing new C plugins for custom languages you should not look so deep.

As an example, with XAnyNormalization=3 once can get the following:

SQL>SPARQL

INSERT IN <http://InternationalNSMs/>
   { <s> <sp> "Índio João Macapá Júnior Tôrres Luís Araújo José" ;
     <ru> "&#1054;&#1085; &#1076;&#1086;&#1073;&#1072;&#1074;&#1080;&#1083; &#1082;&#1072;&#1088;&#1090;&#1086;&#1096;&#1082;&#1080;, &#1087;&#1086;&#1089;&#1086;&#1083;&#1080;&#1083; &#1080; &#1087;&#1086;&#1089;&#1090;&#1072;&#1074;&#1080;&#1083; &#1072;&#1082;&#1074;&#1072;&#1088;&#1080;&#1091;&#1084; &#1085;&#1072; &#1086;&#1075;&#1086;&#1085;&#1100;" . }

INSERT INTO <http://InternationalNSMs/>, 2 (or less) triples -- done

SQL> DB.DBA.RDF_OBJ_FT_RULE_ADD (null, null, 'InternationalNSMs.wb');

Done. -- 0 msec.

SQL>vt_inc_index_db_dba_rdf_obj();

Done. -- 26 msec.

SQL>SPARQL
SELECT *
FROM <http://InternationalNSMs/>
WHERE
  {
    ?s ?p ?o
  }
ORDER BY ASC (str(?o))

s  sp  Índio João Macapá Júnior Tôrres Luís Araújo José
s  ru  &#1054;&#1085; &#1076;&#1086;&#1073;&#1072;&#1074;&#1080;&#1083; &#1082;&#1072;&#1088;&#1090;&#1086;&#1096;&#1082;&#1080;, &#1087;&#1086;&#1089;&#1086;&#1083;&#1080;&#1083; &#1080; &#1087;&#1086;&#1089;&#1090;&#1072;&#1074;&#1080;&#1083; &#1072;&#1082;&#1074;&#1072;&#1088;&#1080;&#1091;&#1084; &#1085;&#1072; &#1086;&#1075;&#1086;&#1085;&#1100;

2 Rows. -- 2 msec.

SQL> SPARQL
SELECT *
FROM <http://InternationalNSMs/>
WHERE
  {
    ?s ?p ?o . ?o bif:contains "'Índio João Macapá Júnior Tôrres Luís Araújo José'" .
  }

s  sp  Índio João Macapá Júnior Tôrres Luís Araújo José

1 Rows. -- 2 msec.

SQL>SPARQL
SELECT *
FROM <http://InternationalNSMs/>
WHERE
  {
    ?s ?p ?o . ?o bif:contains "'Indio Joao Macapa Junior Torres Luis Araujo Jose'" . }

s  sp  Índio João Macapá Júnior Tôrres Luís Araújo José

1 Rows. -- 1 msec.

SQL> SPARQL
SELECT *
FROM <http://InternationalNSMs/>
WHERE
  {
    ?s ?p ?o . ?o bif:contains "'&#1087;&#1086;&#1089;&#1090;&#1072;&#1074;&#1080;&#1083; &#1072;&#1082;&#1074;&#1072;&#1088;&#1080;&#1091;&#1084; &#1085;&#1072; &#1086;&#1075;&#1086;&#1085;&#1100;'" . }

s  ru  &#1054;&#1085; &#1076;&#1086;&#1073;&#1072;&#1074;&#1080;&#1083; &#1082;&#1072;&#1088;&#1090;&#1086;&#1096;&#1082;&#1080;, &#1087;&#1086;&#1089;&#1086;&#1083;&#1080;&#1083; &#1080; &#1087;&#1086;&#1089;&#1090;&#1072;&#1074;&#1080;&#1083; &#1072;&#1082;&#1074;&#1072;&#1088;&#1080;&#1091;&#1084; &#1085;&#1072; &#1086;&#1075;&#1086;&#1085;&#1100;

There was also request for function that normalizes characters in strings as free-text engine will do with XAnyNormalization=3 , the function will be provided as a separate patch and depends on this specific patch.

	See Also:
	Virtuoso Configuration File