Hints and tricks for Oracle and other stuff...

select c.datum,
     extractvalue(value(b), '//tecaj/@oznaka','xmlns="http://www.bsi.si"') oznaka ,
     extractvalue(value(b), '//tecaj/@sifra','xmlns="http://www.bsi.si"') sifra ,
     extractvalue(value(b), '//tecaj','xmlns="http://www.bsi.si"') tecaj
from
(
select
  extractvalue(value(a), '//tecajnica/@datum','xmlns="http://www.bsi.si"') datum,
  extract(value(a),'//tecajnica','xmlns="http://www.bsi.si"') tecajnicaxml
from table (xmlsequence
           (extract(
              URIFACTORY.getUri('http://www.bsi.si/_data/tecajnice/dtecbs-l.xml').getXml()
              , '//DtecBS/tecajnica','xmlns="http://www.bsi.si"'
           ))) a
) c, table (xmlsequence(extract(c.tecajnicaxml,'//tecaj','xmlns="http://www.bsi.si"'))) b         
;