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PolarDB:ST_AsEWKT

Last Updated:Mar 28, 2026

Returns the Well-Known Text (WKT) representation of a geometry or geography object, prefixed with the spatial reference identifier (SRID).

Syntax

text ST_AsEWKT(geometry g1);
text ST_AsEWKT(geography g1);

Parameters

ParameterDescription
g1The geometry or geography object to convert.

Usage notes

  • The output format is SRID=<srid>;<wkt> — for example, SRID=4326;POLYGON((0 0,0 1,1 1,0 0)).

  • WKT does not guarantee full floating-point precision. To preserve exact coordinate values, use ST_AsBinary or ST_AsEWKB instead.

  • To get WKT without the SRID prefix, use ST_AsText.

Supported geometry types:

  • 3D objects

  • Circular strings and curves

  • Polyhedral surfaces

  • Triangles and triangulated irregular network (TIN) surfaces

Examples

Return a WKT string with an SRID

SELECT ST_AsEWKT(ST_GeomFromText('POLYGON((1 1,1 2,2 2,2 1,1 1))',4326));
                st_asewkt
------------------------------------------
 SRID=4326;POLYGON((1 1,1 2,2 2,2 1,1 1))
(1 row)

Return a WKT string without an SRID

SELECT ST_AsEWKT(ST_GeomFromText('POLYGON((1 1,1 2,2 2,2 1,1 1))'));
           st_asewkt
--------------------------------
 POLYGON((1 1,1 2,2 2,2 1,1 1))
(1 row)

See also

  • ST_AsText — returns WKT without the SRID prefix

  • ST_AsBinary — returns WKB without the SRID prefix

  • ST_AsEWKB — returns EWKB with the SRID prefix