ST_AsKML — Return the geometry as a KML element.


text ST_AsKML(geometry geom, integer maxdecimaldigits=15, text nprefix=NULL);

text ST_AsKML(geography geog, integer maxdecimaldigits=15, text nprefix=NULL);


Return the geometry as a Keyhole Markup Language (KML) element. default maximum number of decimal places is 15, default namespace is no prefix.


Using the maxdecimaldigits parameter can cause output geometry to become invalid. To avoid this use ST_ReducePrecision with a suitable gridsize first.


Requires PostGIS be compiled with Proj support. Use PostGIS_Full_Version to confirm you have proj support compiled in.


Availability: 1.2.2 - later variants that include version param came in 1.3.2


Enhanced: 2.0.0 - Add prefix namespace, use default and named args


Changed: 3.0.0 - Removed the "versioned" variant signature


AsKML output will not work with geometries that do not have an SRID

This function supports 3d and will not drop the z-index.


SELECT ST_AsKML(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326));

		<Polygon><outerBoundaryIs><LinearRing><coordinates>0,0 0,1 1,1 1,0 0,0</coordinates></LinearRing></outerBoundaryIs></Polygon>

		--3d linestring
		SELECT ST_AsKML('SRID=4326;LINESTRING(1 2 3, 4 5 6)');
		<LineString><coordinates>1,2,3 4,5,6</coordinates></LineString>

See Also