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:     

CONSTRUCT
{
    ?fancytitle
}
WHERE
{
  SELECT (group_concat(?title ; separator = " ") AS ?fancytitle) WHERE { 
    GRAPH ?graph {
        dc:relation+ ?relation .
      ?relation dc:title ?title .
    }
  }
}

The above works fine on your endpoint