Policies for indexing categories
There are two kinds of policies:
- Path policies are based on the path of the category.
- Ordinal policies are based on the ordinal of the category.
Policies are "consulted" with during indexing, for deciding whether a category should
be added to the index or not. The two kinds of policies can be used for different purposes.
For example, path policies dictates which categories can participate in a drill-down operation,
while ordinal policies affect which can be accumulated (e.g. counted).