https://issues.apache.org/jira/browse/JENA-1963
Try
sparql --strict
sparql --engine=ref
sparql --optimize=off
The optimization rule that sees "FILTER(?n = ?m)" and tries to make it a
join goes wrong because of the interaction with substitution.
BTW:
https://afs.github.io/substitute.html
lists several problems with NOT EXISTS and gives a solution.
The solution would also work for parameterized queries if the
scope-renaming is omitted.
Andy
On 03/05/2021 16:43, Olivier Dameron wrote:
Dear jena users,
I tried to replicate the negation examples from
https://www.w3.org/TR/sparql11-query/#idp899488 (section 8.3.3 Examples:
Inner FILTERs).
I got [(a, 1), (b, 3.0)] for both versions of the query whereas I
expected to get only [(b, 3.0)] with the FILTER NOT EXISTS.
Same result with jena-3.17
Rdflib returns the same results as the W3C page.
Am I missing something?
Thank you
olivier
DATA:
-----
@prefix : <http://example.com/> .
:a :p :v1 .
:a :q :v1 .
:a :q :v2 .
:b :p :v3 .
:b :q :v4 .
:b :q :v5 .
QUERY 1 (expected: [(b, 3.0)] ; returned: [(a, 1), (b, 3.0)]):
--------------------------------------------------------------
PREFIX : <http://example.com/>
SELECT *
WHERE {
?x :p ?n .
FILTER NOT EXISTS {
?x :q ?m .
FILTER(?n = ?m)
}
}
QUERY 2 (correctly returned [(a, 1), (b, 3.0)]):
------------------------------------------------
PREFIX : <http://example.com/>
SELECT *
WHERE {
?x :p ?n .
MINUS {
?x :q ?m .
FILTER(?n = ?m)
}
}
