How to add extra-column to RDF_QUAD with access from sparql query?

Virtuoso Universal Server
1

Hi! From here 1.4.13. Do you support additional metadata for triples, such as time-stamps, security tags etc? i’ve found, that it’s possible to add some extra data to triple… and create some kind of megaQuad :).

I need to store somewhere SingletonProperty Uri for storing metadata (in other words - id of every triple).

We use singleton property methodology from here Don’t like RDF Reification? Making Statements about Statements Using Singleton Property | PPT .

Now we have such queries:

SELECT * WHERE {
  GRAPH ?g {
  ?resourceUri ?spUri ?value.
  ?spUri rdf:singletonPropertyOf ?predicate.
  }
}

But it would be so nice to have queries like this:

SELECT * WHERE {
  GRAPH ?g {
      ?resourceUri ?predicate ?value ?spUri.
  }
}

Is this possible to add some extra column to RDF_QUAD and change base sparql pattern in virtuoso?

Give me the way, please :slight_smile: