For both the SOAP and VG dashboards, we expected a direct relationship between the items and the group: P-195 (collection) is on each artwork item ; P-400 (platform) is on each game item, etc.
The idea was to have a very simple interface (ie, simple parameters) so that folks with little SPARQL-fu could easily use it.
By doing so, however, the kind of grouping possible was arbitrarily restricted.
Typically, in some use cases, the grouping is 1 (or more item away). For example, building a coverage dashboard of French churches per department: on the church item, P-131 points to the city, and from the city P-131 points to the department.
(Added complexity here is that the city will have more than one value of P-131, which means we need to further restrict in SPARQL).
The general use case here is overall reasonable, however I’m unsure how to build a path towards this which maintains the original goal of accessibility:
- |grouping_property=P195 → easy ;
- |grouping_sparql=?entity wdt:P195 ?grouping . → less so
(Would also need to think through how to reconstruct the no-group query if allowing 'free-form' input).