From 8bde217e7c24a4b61b57a71d0453f185bff76f71 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Carlos=20Matall=C3=ADn?= Date: Wed, 28 Oct 2015 12:37:51 +0100 Subject: [PATCH] doc: handling_geospatial_data --- doc/handling_geospatial_data.md | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/doc/handling_geospatial_data.md b/doc/handling_geospatial_data.md index e19da01a..421978eb 100644 --- a/doc/handling_geospatial_data.md +++ b/doc/handling_geospatial_data.md @@ -2,15 +2,18 @@ Handling geospatial data through the SQL API is easy! By default, *the_geom* is returned straight from the database, in a format called Well-Known Binary. There are a handful of ways you can transform your geometries into more useful formats. - The first, is to use the format=GeoJSON method described above. Others can be handled through your SQL statements directly. For example, enclosing your the_geom in a function called [ST_AsGeoJSON](http://www.postgis.org/documentation/manual-svn/ST_AsGeoJSON.html) will allow you to use JSON for your data but a GeoJSON string for your geometry column only. Alternatively, using a the [ST_AsText](http://www.postgis.org/documentation/manual-svn/ST_AsGeoJSON.html) function will return your geometry as Well-Known Text. -
ASGEOJSON
+### ST_AsGeoJSON + +#### Call + ```bash https://{account}.cartodb.com/api/v2/sql?q=SELECT cartodb_id,ST_AsGeoJSON(the_geom) as the_geom FROM {table_name} LIMIT 1 ``` -
RESULT
+#### Result + ```javascript { time: 0.003, @@ -24,13 +27,16 @@ https://{account}.cartodb.com/api/v2/sql?q=SELECT cartodb_id,ST_AsGeoJSON(the_ge } ``` +### ST_AsText + +#### Call -
ASTEXT
```bash https://{account}.cartodb.com/api/v2/sql?q=SELECT cartodb_id,ST_AsText(the_geom) FROM {table_name} LIMIT 1 ``` -
RESULT
+#### Result + ```javascript { time: 0.003, @@ -48,7 +54,8 @@ More advanced methods exist in the PostGIS library to extract meaningful data fr All data returned from *the_geom* column is in WGS 84 (EPSG:4326). You can change this quickly and easily on the fly using SQL. For example, if you desire geometries in the Hanoi 1972 (EPSG:4147) projection, you could [ST_Transform](http://www.postgis.org/docs/ST_Transform.html), -
ASTEXT
+### ST_Transform + ```bash https://{account}.cartodb.com/api/v2/sql?q=SELECT ST_Transform(the_geom,4147) FROM {table_name} LIMIT 1 ```