SPARQL triples with no variables

[Graham Matthews]

Hi

I have a couple of questions about the semantics of some unusual SPARQL
queries.

What is the semantics of the following SPARQL query?

select $x from graph_iri
where
{
        $x a some_iri_1.
        some_iri_2 some_iri_3 some_iri_4 
}

where all of the some_iri_i's are distinct, and the graph contains NO triples 
of the form

        some_iri_2 some_iri_3 some_iri_4 

?

Is the answer empty or all $x's that satisfy the first triple?

Similarly what is the semantics of the following query?

select $x from graph_iri
where
{
        $x a some_iri_1.
        $y some_iri_3 some_iri_4 
}

where all of the some_iri_i's are distinct, and the graph contains NO triples
that match the second 
pattern?

thanks
graham