Mappings to external vocabularies/ontologies are not correctly added

[dalito]

In nfdi4cat/voc4cat#117 we wanted to add a skos:broader mapping via the Additional Concept Features sheet.

We defined three mappings:

Concept IRI*	...	Broader Matches
https://w3id.org/nfdi4cat/voc4cat_0005056		https://www.w3.org/ns/sosa/Sample
https://w3id.org/nfdi4cat/voc4cat_0005057		https://www.w3.org/ns/sosa/Sample
https://w3id.org/nfdi4cat/voc4cat_0005058		https://www.w3.org/ns/sosa/Sample

However, the mappings appeared in wrong turtle files (for the wrong concept):

<https://w3id.org/nfdi4cat/voc4cat_0000016>
    a skos:Concept ;
    dcterms:identifier "voc4cat_0000016"^^xsd:token ;
    rdfs:isDefinedBy <https://www.w3.org/TR/2010/NOTE-curie-20101216/> ;
    skos:broadMatch <https://www.w3.org/ns/sosa/Sample> ;
    skos:broader <https://w3id.org/nfdi4cat/voc4cat_0000186> ;
    skos:definition "The form in which the catalyst is introduced to the reaction chamber. This can include e.g., powders, pellets or thin films deposited on a substrate."@en ;
    skos:inScheme <https://w3id.org/nfdi4cat/voc4cat_> ;
    skos:prefLabel "catalyst form"@en ;
.

The other SOSA mapping were added (also wrongly) to voc4cat_0000019 and voc4cat:0007037. The three concepts to which the mapping was added were in the first three lines of the Concepts sheet. Obviously the first column in Additional Concept Features sheet is not correctly used as key to generate the mapping for the given concept.

[dalito]

The reason for the problem is the way the sheets "Concepts" and "Additional Concept Features" are parsed. Both are read in parallel row by row. So the same IRI must be present in the same row in both sheets. Whenever the order of rows is different, the mappings are assigned wrongly because the mapping happens in principle by row and not by IRI. This behavior is inherited from the code we built upon and it should of course change.

The idea is to use the IRIs as keys to link the rows in both sheets correctly. Then it is also possible to only add the IRIs that you want to provide mappings for. Moreover, both sheets could use completely different ordering. This solution would not even break backward compatibility.