Fall back of the reverse geocoder

Question

Hi All,
Looking at the results of reverse geocoding, it seems that it’s only based on the street_segment geometries with a nearest neighbor search without considering the actual distance. Looking at the oracle spatial geocoder schema from NAVTEQ samples, it seem that only street segment are spatially indexed in the geocoder and the GC_AREA table doesn’t seem to even have the spatial boundaries (it just have the centroid information).
I wanted to know if there was a reason for that behavior/design, or even a fix in later version of Oracle Spatial geocoder (we are using 10.2.0.5)
Typically ReverseGeocoders on the market, when the point is too far from street segment, will fallback and use the spatial boundaries (municipality boundaries or state/province boundaries),
to perform Point in polygon operation like sdo_contains to know if the point falls into a specific polygon.
In the case of my customer, this is a huge issue, as he expect to reverse geocode in area where there are few or no street and he expect to have data from limited amount of country.
Using reverse geocoding (implemented as nearest neighbor) in that case will give inconsistent result, that could be several kilometers or even hundred kilometers, from the point clicked.
The easy work around I see would be to limit the distance accepted between the point clicked and the segment returned by the reverse geocoding,
But that would have the side effect that if I click in a specific Municipality or province, I would not be able to get reverse geocoding result.
The same way, since reverse geocoding take the nearest segment, it can return a segment in a municipality even if the point clicked is in another municipality,
Thanks for the help,
Pierre.

Answer 1

Hi
You would need to review the logs (MIVR/MCVD logs) to determine the cause of this failure:
They are in subfolders of c:\program files\wfavvid\log
Feel free to post them up.
Aaron