Stability by Feature Type
Stability and traceability
Depending on the feature type, unique IDs registered to GERS are intended to be stable — within a reasonable tolerance of error — across multiple Overture releases. When stability is not possible, we will attempt to provide traceability in a GERS changelog. For example:
- a single road segment is bisected by a new road and becomes two road segments: 1 unique ID → 2 new unique IDs;
- a large building footprint is determined to be four smaller buildings when a higher resolution dataset becomes available: 1 unique ID → 4 new unique ID;
- a building is shifted 10 meters to the west when higher resolution imagery is made available: the unique ID is preserved for that feature.
The table below indicates which Overture feature types are intended to be stable from release to release.
| Theme | Type | Stable ID |
|---|---|---|
| addresses | address | No |
| base | infrastructure | No |
| base | land | No |
| base | land_cover | No |
| base | land_use | No |
| base | water | No |
| buildings | building | Yes |
| buildings | building_part | No |
| divisions | division | Yes |
| divisions | division_area | No |
| divisions | division_boundary | No |
| places | place | Yes |
| transportation | segment | Yes |
| transportation | connector | Yes |