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Quickstart
If you are using the set of APIs and libraries that CartoDB offers, and you are handling your data with the SQL API, you can make your data visible in your maps by geocoding the dataset programatically. The set of isoline functions allow you to calculate the area which can be reached by travelling a given distance or time, useful for geospatial analysis, such as Trade Area Analysis.
Here is an example of how to geocode a single country:
https://{username}.cartodb.com/api/v2/sql?q=SELECT cdb_geocode_admin0_polygon('USA')&api_key={Your API key}
In order to geocode an existent CartoDB dataset, an SQL UPDATE statement must be used to populate the geometry column in the dataset with the results of the Geocoding API. For example, if the column where you are storing the country names for each one of our rows is called country_column, run the following statement in order to geocode the dataset:
https://{username}.cartodb.com/api/v2/sql?q=UPDATE {tablename} SET the_geom = cdb_geocode_admin0_You can use the isoline functions to retrieve, for example, isochrone lines from a certain location, specifying the mode and the ranges that will define each of the isolines. The following query calculates isolines for areas that are 5, 10 and 15 minutes (300, 600 and 900 seconds, respectively) away from the location by following a path defined by car routing.
polygon({country_column})&api_key={Your API key}
https://{username}.cartodb.com/api/v2/sql?q=SELECT cdb_isochrone('POINT(-3.70568 40.42028)'::geometry, 'car', ARRAY[300,600,900]::integer[])&api_key={Your API key}
Notice that you can make use of Postgres or PostGIS functions in your Data Services API requests, as the result is a geometry that can be handled by the system. For example, suppose you need to retrieve the centroid of a specific country, you can wrap the resulting geometry from the geocoder functions inside the PostGIS ST_Centroid function:
https://{username}.cartodb.com/api/v2/sql?q=SELECT ST_Centroid(cdb_geocode_admin0_polygon('USA'))&api_key={Your API key}
Using Mapzen Services
You can use Mapzen as the service provider for geocoding and routing with CartoDB. This enables you to take advantage of the geocoding search features, and the turn-by-turn routing service that Mapzen offers. To use these features through CartoDB, all you need is a Mapzen API Key.
Integration with Mapzen varies, depending on your account plan:
- Enterprise account users will receive a Mapzen API Key through CartoDB
- All other account plans can go to the Mapzen Developers page to retrieve an API key. This is a free integration that allows you to access the Mapzen services by connecting your GitHub account
Tip You can also use Mapzen basemaps by integrating with their API. This is useful is you want to include a vector tile service basemap with your CartoDB map. To include their external basemaps, define the URL and Mapzen attributions in the HTTP data layer of your MapConfig file. Currently, Mapzen vector tile basemaps are only supported via the API, and are not available through the CartoDB Editor.