I am using the freely available geonames data locally to do autocomplete searches during the sign up stage on one of my websites.
I am having trouble working out the best way to make the form more user friendly by auto selecting a geoname based on their IP address and also be able to lookup a geoname based on the postcode data.
The problem is that I can't see a way to easily link an IP range or a postal code to a geoname. So what is the best practice here? Do I just run a separate query to lookup the nearest geoname by long/lat against the postcode or IP address?