SPARQL functions in CONSTRUCT/WHERE

Question

I mostly use SPARQL SELECT while working on a query for debugging purposes but in the end I want to use the final result it in a CONSTRUCT way; as I want to work with a grap

Answer 1

With the help of my colleague we got it to work, UNION and GROUP BY are essential. This query puts the string together for all locah:ArchivalResource in the graphs:

CONSTRUCT
{
  ?archresource skos:hiddenLabel ?supertitle
}
WHERE
{
  SELECT ?archresource  (group_concat(?title ; separator = ", ") AS ?supertitle) WHERE {
    GRAPH ?graph {
      {
        SELECT ?title ?archresource WHERE {
          GRAPH ?graph {
            {
              ?archresource a locah:ArchivalResource ;
              dc:title ?title .
            } UNION
            {
              ?archresource dc:relation+ ?relation .
              ?relation dc:title ?title .
            }
          }
        }
      }
    }
  } GROUP BY ?archresource
}