I'm trying to use a Rule to come up with the COUNT of all instances of an object that is stored in a nested collection three levels deep. My data structure looks like:
I want to be able to count all instances of the TagTemplates object that have a zero stored in its Order Property. My thought was that I would simply be able to use a Rule that would reference all instances of Stations object, Units object, and TagTemplates object (within their respective collections) and return the count of all TagTemplates that have an Order value of zero. A rule something like:
StationsCollection Property :> All UnitsCollection Property :> All TagTemplatesCollection Property
However, when I go to the property browser to specify the collection to pass to the COUNT function, it only lets me go two levels deep. As you can see below, when I select "All UnitsCollection", there is no way to expand to the next level down.
Am I doing something wrong, or is there a better way to do this?