ST_AsGeoJSON¶
TL;DR¶
ST_AsGeoJSON serializes a geometry as a GeoJSON VARCHAR.
Syntax¶
ST_AsGeoJSON(geom)
ST_AsGeoJSON(geom, maxdecimaldigits)
Arguments¶
geom is a GEOMETRY or GEOMETRY32 value. maxdecimaldigits is an INT64 maximum number of coordinate decimal digits.
Return Value¶
Returns a VARCHAR containing a GeoJSON geometry object.
Usage Notes¶
Use maxdecimaldigits to round coordinate output. Without it, the function uses its default coordinate precision.
Examples¶
DROP DATABASE IF EXISTS geo_st_asgeojson_demo;
CREATE DATABASE geo_st_asgeojson_demo;
USE geo_st_asgeojson_demo;
SELECT ST_AsGeoJSON(ST_GeomFromText('POINT(1 2)')) AS point_json;
SELECT ST_AsGeoJSON(ST_GeomFromText('POINT(1.23456 2.34567)'), 2) AS rounded_json;
SELECT ST_AsGeoJSON(ST_GeomFromText('POLYGON((0 0,4 0,4 4,0 4,0 0))')) AS polygon_json;
DROP DATABASE geo_st_asgeojson_demo;