X-Git-Url: https://git.openstreetmap.org./nominatim.git/blobdiff_plain/8e19336f49e508ff9587be04ec8b5b10fa77daad..8c3a0efe8b75a06279998e66a932d8a56c483961:/data-sources/country-grid/README.md?ds=sidebyside diff --git a/data-sources/country-grid/README.md b/data-sources/country-grid/README.md index c94929af..5c036bac 100644 --- a/data-sources/country-grid/README.md +++ b/data-sources/country-grid/README.md @@ -31,7 +31,7 @@ Each place is assigned partition, which is a number 0..250. 0 is fallback/other. During place indexing (`sql/functions.sql: placex_insert()`) a place is assigned the partition based on its country code (`sql/functions.sql: get_partition(country_code)`). It checks in the `country_name` table. -Most countries have their own parition, some share a partition. Thus partition counts vary greatly. +Most countries have their own partition, some share a partition. Thus partition counts vary greatly. Several database tables are split by partition to allow queries to run against less indices and improve caching. @@ -45,13 +45,13 @@ Several database tables are split by partition to allow queries to run against l ## Data files -### `data/country_name.sql` +### data/country_name.sql Export from existing database table plus manual changes. `country_default_language_code` most taken from [https://wiki.openstreetmap.org/wiki/Nominatim/Country_Codes](), see `utils/country_languages.php`. -### `data/country_osm_grid.sql` +### data/country_osm_grid.sql `country_grid.sql` merges territories by country. Then uses `function.sql: quad_split_geometry` to split each country into multiple [Quadtree](https://en.wikipedia.org/wiki/Quadtree) polygons for faster point-in-polygon lookups.