Null function not behaving correctly

[alloka]

Hello All,

So I'm trying to use the null function to check the non-existence of a json entity in my data , but it is not behaving correctly:

My data is as follows:
[{"id":"0","labels":["Student"],"properties":{"id":20}},{"type":"stay","id":"1","labels":["Sport"],"properties":{"sport_id":100,"sport_name":"Tennis"}},{"type":"node","id":"2","labels":["Student"],"properties":{"name":"Venus Williams","id":10,"sport":100}}]

and my mappings are the following:
prefixes:
rr: http://www.w3.org/ns/r2rml#
foaf: http://xmlns.com/foaf/0.1/
xsd: http://www.w3.org/2001/XMLSchema#
rdfs: http://www.w3.org/2000/01/rdf-schema#
Airport: http://example.org/Airport/
ontology: http://data.sfgov.org/ontology/
grel: http://users.ugent.be/~bjdmeest/function/grel.ttl#
exfunc: http://example.com/idlab/function/
ex: http://www.example.org/
idlab-fn: https://w3id.org/imec/idlab/function#`

mappings:
episode:
sources:
- [data.json~jsonpath, "$.[*]"]
s: ex:$(id)
condition:
function: idlab-fn:isNull
parameters:
- [grel:valueParameter, $(type)]
po:
- p: a
o: ex:Node

The output is:

<http://www.example.org/0> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.example.org/Node> . <http://www.example.org/1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.example.org/Node> . <http://www.example.org/2> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.example.org/Node> .

while the expected output should return only the first triple

Also, is there any way to use the not null function as well in RML?

Best regards,
Ali.

[bjdmeest]

Could your paste the RML mapping file and properly format the yarrrml code? hard to bugfix this.

For the not null function: you can nest the not function with the null function, for an example of a nesting in a condition, see https://github.com/RMLio/yarrrml-parser/blob/development/test/condition-on-mapping-nested/mapping.yarrrml

[alloka]

Dear @bjdmeest Ben,

so I attached both the yaml and mappings file as txt files:

bug_yaml.txt
mappings.txt

Best regards,
Ali.