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

Yes this is possible

You can't use expressions directly in a CONSTRUCT template but you can assign the variable in the WHERE clause either via a SELECT expression in a sub-query or using BIND.

In your case as GROUP_CONCAT is an aggregate it can only be a SELECT expression so you just need to put your entire SELECT as a sub-query e.g.

PREFIX dc: <http://purl.org/dc/elements/1.1/>    

CONSTRUCT
{
  <http://data.staatsarchiv-bs.ch/id/archivalresource/CH-000027-1/pa-633c-a-312-fasc-163> <http://fancyTitle> ?fancytitle
}
WHERE
{
  SELECT (group_concat(?title ; separator = " ") AS ?fancytitle) WHERE { 
    GRAPH ?graph {
      <http://data.staatsarchiv-bs.ch/id/archivalresource/CH-000027-1/pa-633c-a-312-fasc-163>  dc:relation+ ?relation .
      ?relation dc:title ?title .
    }
  }
}

The above works fine on your endpoint

Answer 2

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
}