SELECT idCategoria, NombreCategoria, XMLQuery(
'for $x in collection("CatalogoCD")/catalogo/cd
where $x/artistas/artista/@origen = "España"
return 
  <cd id = "{$x/@id}">
    <id>{$x/@id}</id>
    {$x/artistas/artista}
  </cd>'
PASSING CatalogoCD RETURNING CONTENT
) AS AutorEspaña
FROM Categorias