Geometric consistency in the Divisions hierarchy

[alekaelin]

Hi Overture team,

We are currently evaluating the Overture "Divisions" dataset as a potential global administrative boundary source for geospatial analytics.

I have a question regarding the relationship between administrative levels. The documentation describes the logical hierarchy through parent_division_id and hierarchies, but I couldn't find information about the geometric relationship between polygons at different levels.

Specifically, are there any guarantees that:

• Child polygons form an exact partition of their parent polygon?
• The union of all child polygons is geometrically identical to the parent polygon?
• Boundaries are topologically aligned across hierarchy levels (i.e., no gaps or overlaps between adjacent levels)?

Or should the hierarchy be interpreted as a logical/administrative relationship only, without guarantees that geometries align perfectly across levels?

Moreover, do neighboring polygons form a seamless coverage within the same administrative level (i.e., no gaps or overlaps between adjacent division polygons)?

Thank you in advance for your help!