QVT13 — QVTo: Relationship between QVTo Mapping and QVTr Relation

8.1.4 states "a mapping operation is always a refinement of an implicit relation" but 8.2.15 defines "refinedRelation: Relation [0..1] The refined relation, if any." Clearly a contradiction.

8.1.4. provides the REL_PackageToSchema example of how an implicit relation might be defined, but no other examples or synthesis rules are supplied.

enforce and checkonly appear in the REL_PackageToSchema example indicating that these define execution mode of a QVTo trnasformation, but there does not appear to be any description of how a transformation might be executed to for instance update an output model. Perhaps the 'output' parameter is 'inout' for create/update but 'out' for create/overwrite.

8 Unclear mapping operation characteristics

8.1.4 states "a mapping operation is always a refinement of an implicit relation" but 8.2.15 defines "refinedRelation: Relation [0..1] The refined relation, if any." Clearly a contradiction.

8.1.4. provides the REL_PackageToSchema example of how an implicit relation might be defined, but no other examples or synthesis rules are supplied.

enforce and checkonly appear in the REL_PackageToSchema example indicating that these define execution mode of a QVTo trnasformation, but there does not appear to be any description of how a transformation might be executed to for instance update an output model. Perhaps the 'output' parameter is 'inout' for create/update but 'out' for create/overwrite.

Discussion

The aspiration that every QVTo mapping has an underlying QVTr relation is fairly dubious. But there is no point respecifying until some prototyping feedback is available.