13 KiB
13 KiB
Named places geocoder
Function
Receives an array of city names (with optional values for the countries and/or the administrative regions to which they belong) and returns point geometries for each row if the geocoding process was successful.
Usage example
SELECT (geocode_namedplace(Array['sunapee', 'sunapeeee', 'New York City'], 'USA')).*
Creation steps
- Download the
allCountries
andalternateNames
tables from the source - In order to clean the files from characters that may provoke issues when importing to CARTO, please run in your terminal:
sed 's/"//' filename.txt > filename.out.txt
- Import the zipped files for
allCountries
andalternateNames
once processed - Generate the
global_cities_points_limited
andglobal_cities_alternates_limited
tables - Run the
sql/build_data_table.sql
script to build theglobal_cities_points_limited
table
Tables
global_cities_points_limited
Table structure
Table "public.global_cities_points_limited"
Column | Type | Modifiers | Storage | Stats target | Description
----------------------+--------------------------+-----------------------------------------------------------------------+----------+--------------+-------------
geoname_id | double precision | | plain | |
name | text | | extended | |
asciiname | text | | extended | |
altnames | text | | extended | |
featclass | text | | extended | |
featcode | text | | extended | |
iso2 | text | | extended | |
cc2 | text | | extended | |
admin1 | text | | extended | |
admin2 | text | | extended | |
admin3 | text | | extended | |
admin4 | text | | extended | |
population | double precision | | plain | |
gtopo30 | integer | | plain | |
the_geom | geometry(Point,4326) | | main | |
created_at | timestamp with time zone | not null default now() | plain | |
updated_at | timestamp with time zone | not null default now() | plain | |
the_geom_webmercator | geometry(Geometry,3857) | | main | |
cartodb_id | integer | not null default nextval('points_cities_le_cartodb_id_seq'::regclass) | plain | |
lowername | text | | extended | |
Current indexes
Indexes:
"points_cities_le_pkey" PRIMARY KEY, btree (cartodb_id)
"points_cities_le_cartodb_id_key" UNIQUE CONSTRAINT, btree (cartodb_id)
"idx_global_cities_points_lim_a" btree (lowername, iso2)
"idx_global_cities_points_lim_admin1" btree (admin1)
"idx_global_cities_points_lim_geoname_id" btree (geoname_id)
"points_cities_le_the_geom_idx" gist (the_geom)
"points_cities_le_the_geom_webmercator_idx" gist (the_geom_webmercator)
global_cities_alternates_limited
Table structure
Table "public.global_cities_alternates_limited"
Column | Type | Modifiers | Storage | Stats target | Description
----------------------+--------------------------+---------------------------------------------------------------------------------------+----------+--------------+-------------
geoname_id | integer | | plain | |
name | text | | extended | |
the_geom | geometry(Geometry,4326) | | main | |
created_at | timestamp with time zone | not null default now() | plain | |
updated_at | timestamp with time zone | not null default now() | plain | |
the_geom_webmercator | geometry(Geometry,3857) | | main | |
preferred | boolean | | plain | |
lowername | text | | extended | |
cartodb_id | integer | not null default nextval('global_cities_alternates_limited_cartodb_id_seq'::regclass) | plain | |
admin1_geonameid | integer | | plain | |
iso2 | text | | extended | |
admin1 | text | | extended | |
Current indexes
Indexes:
"global_cities_alternates_limited_pkey" PRIMARY KEY, btree (cartodb_id)
"global_cities_alternates_limited_the_geom_idx" gist (the_geom)
"global_cities_alternates_limited_the_geom_webmercator_idx" gist (the_geom_webmercator)
"idx_global_cities_alternates_limited_admin1" btree (admin1)
"idx_global_cities_alternates_limited_admin1_geonameid" btree (admin1_geonameid)
"idx_global_cities_alternates_limited_lowername" btree (lowername)
Related functions
geocode_namedplace
Schema | Name | Result data type | Argument data types | Type
--------+--------------------+-------------------------------------+----------------------------------------------------+--------
public | geocode_namedplace | SETOF geocode_namedplace_v1 | places text[] | normal
public | geocode_namedplace | SETOF geocode_admin1_country_v1 | places text[], admin1s text, inputcountry text | normal
public | geocode_namedplace | SETOF geocode_admin1_country_v1 | places text[], admin1s text[], inputcountry text | normal
public | geocode_namedplace | SETOF geocode_admin1_country_v1 | places text[], admin1s text[], inputcountry text[] | normal
public | geocode_namedplace | SETOF geocode_namedplace_country_v1 | places text[], country text[] | normal
public | geocode_namedplace | SETOF geocode_admin_country_v1 | places text[], inputcountry text | normal
geocode_namedplace_country
Schema | Name | Result data type | Argument data types | Type
--------+----------------------------+-------------------------------------+-------------------------------+--------
public | geocode_namedplace_country | SETOF geocode_namedplace_country_v1 | places text[], country text[] | normal
Response data types
- geocode_namedplace_country_v1:
CREATE TYPE geocode_namedplace_country_v1 AS (q TEXT, c TEXT, geom GEOMETRY, success BOOLEAN);
Data Sources
- Geonames free gazzeter data.
allCountries.zip
file available here.alternateNames.zip
file available here.- Coverage: global
- Geometry type: point
Fields metadata (from GeoNames database)
column name | meaning |
---|---|
geonameid | integer id of record in geonames database |
name | name of geographical point (utf8) varchar(200) |
asciiname | name of geographical point in plain ascii characters, varchar(200) |
alternatenames | alternatenames, comma separated, ascii names automatically transliterated, convenience attribute from alternatename table, varchar(10000) |
latitude | latitude in decimal degrees (wgs84) |
longitude | longitude in decimal degrees (wgs84) |
feature class | see http://www.geonames.org/export/codes.html, char(1) |
feature code | see http://www.geonames.org/export/codes.html, varchar(10) |
country code | ISO-3166 2-letter country code, 2 characters |
cc2 | alternate country codes, comma separated, ISO-3166 2-letter country code, 200 characters |
admin1 code | fipscode (subject to change to iso code), see exceptions below, see file admin1Codes.txt for display names of this code; varchar(20) |
admin2 code | code for the second administrative division, a county in the US, see file admin2Codes.txt; varchar(80) |
admin3 code | code for third level administrative division, varchar(20) |
admin4 code | code for fourth level administrative division, varchar(20) |
population | bigint (8 byte int) |
elevation | in meters, integer |
dem | digital elevation model, srtm3 or gtopo30, average elevation of 3''x3'' (ca 90mx90m) or 30''x30'' (ca 900mx900m) area in meters, integer. |
timezone | the timezone id (see file timeZone.txt) varchar(40) |
modification date | date of last modification in yyyy-MM-dd format |
Testing
In order to test the data and the functions created under the script avaialble in this folder, you will need to run bash test.sh
from test/data
and test/functions
.
Known issues
- Admin1 column with null rows doesn't return a result: https://github.com/CartoDB/data-services/issues/147
- The geocoding function is using a deprecated table:
admin1_decoder
instead of the newadmin1_synonyms
. Related issue: https://github.com/CartoDB/data-services/issues/148 - The name of the countries added in a column are not being sanitized https://github.com/CartoDB/cartodb/issues/3392
- The generation script for
global_cities_alternates_limited
is missing. - Needs a better approach for synonyms and normalisation
Historic:
- [01/12/2015]:
- Removed geocoder function. Check /extensions instead.
- [19/10/2015]:
- Updates README with process description and update setup scripts
- [08/10/2015]:
- Added response data types
- [14/07/2015]:
- Updated README: Known issues
- Added tests
- [24/06/2015]:
- Added section "Known issues"
- Added table, functions and indexes information
- Reviewed functions in the sql file. Added this one
- [23/06/2015]:
README.md
file generated- Added structure for
/test