* It shows what NOT is (basically allows you to say things like "give me all the states that are not Alabama").
* Uses the new HAVING clause.
* Seems to be a nice use case for count and/or subqueries i.e. the ability to execute an outer query and plug the results into the inner query finally makes sense.
select $s $p $x count (
select $type
from <rmi://.../server1#foo>
where $s $p $type
and not($type <rdf:type> $x ))
from <rmi://.../server1#foo>
where $r <rdf:type> <owl:Restriction>
and $r <owl:onProperty> $p
and $r <owl:allValuesFrom> $x
and $s $p $o2
having $k0 <tucana:occursMoreThan> '0'^^<xmlschema:nonNegativeInteger>
order by $s ;
$k0 is the variable binding for the COUNT - we should offer a way to explicitly bind aggregates to a variable.
Another new feature that Paul's been working on, querying only URIs, makes use of virtual graphs and magical predicates like our data typing support.
Buona sera, ma in ITQL รจ poissibile scrivere l'espressione and not($a <...> <...>)? A me da problemi, vorrei dei chiarimenti. Grazie
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