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.
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, P131 points to the cityThe idea was to have a very simple interface (ie, and from the city P131 points to the departmentsimple 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).