X-Git-Url: https://git.openstreetmap.org./nominatim.git/blobdiff_plain/dea1d67d03fb3a28eb70c2e1740c1e1470b30261..1d2f4264a2453ac83492213aff37f4d294845f68:/docs/develop/Postcodes.md diff --git a/docs/develop/Postcodes.md b/docs/develop/Postcodes.md index 8b532162..ff36b0dd 100644 --- a/docs/develop/Postcodes.md +++ b/docs/develop/Postcodes.md @@ -1,18 +1,21 @@ # Postcodes in Nominatim -The blog post [Nominatim and Postcodes](https://www.openstreetmap.org/user/lonvia/diary/43143) -describes the new handling in Nominatim 3.1. +The blog post +[Nominatim and Postcodes](https://www.openstreetmap.org/user/lonvia/diary/43143) +describes the handling implemented since Nominatim 3.1. -Postcode centroids (aka 'calculated postcodes') are generated by looking at all postcodes of -a country, grouping them and calculating the geometric centroid. There is currently no logic -to deal with extreme outliers (typos or other mistakes in OSM data). There is also no check -if a postcodes adhere's to a countries format, e.g. if Swiss postcodes are 4 digits. +Postcode centroids (aka 'calculated postcodes') are generated by looking at all +postcodes of a country, grouping them and calculating the geometric centroid. +There is currently no logic to deal with extreme outliers (typos or other +mistakes in OSM data). There is also no check if a postcodes adheres to a +country's format, e.g. if Swiss postcodes are 4 digits. ## Regular updating calculated postcodes -The script to rerun the calculation is `build/utils/update.php --calculate-postcodes` and -runs once per night on nominatim.openstreetmap.org. +The script to rerun the calculation is +`build/utils/update.php --calculate-postcodes` +and runs once per night on nominatim.openstreetmap.org. ## Finding places that share a specific postcode @@ -20,10 +23,12 @@ runs once per night on nominatim.openstreetmap.org. In the Nominatim database run ```sql - SELECT osm_type, osm_id, class, type, st_x(centroid) as lon, st_y(centroid) at lat - FROM placex - WHERE country_code='fr' - AND upper(trim (both ' ' from address->'postcode')) = '33210'; +SELECT address->'postcode' as pc, + osm_type, osm_id, class, type, + st_x(centroid) as lon, st_y(centroid) as lat +FROM placex +WHERE country_code='fr' + AND upper(trim (both ' ' from address->'postcode')) = '33210'; ``` Alternatively on [Overpass](https://overpass-turbo.eu/) run the following query