ST_GeomFromText - Amazon Redshift
SyntaxArgumentsReturn typeExamples
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ST_GeomFromText

ST_GeomFromText constructs a geometry object from a well-known text (WKT) representation of an input geometry.

ST_GeomFromText accepts 3DZ, 3DM, and 4D where the geometry type is prefixed with Z, M, or ZM, respectively.

Syntax

ST_GeomFromText(wkt_string)
ST_GeomFromText(wkt_string, srid)

Arguments

wkt_string

A value of data type VARCHAR that is a WKT representation of a geometry.

You can use the WKT keyword EMPTY to designate an empty point, a multipoint with an empty point, or a geometry collection with an empty point. The following example creates a multipoint with one empty and one nonempty point. 

ST_GeomFromEWKT('MULTIPOINT(1 0,EMPTY)');
srid

A value of data type INTEGER that is a spatial reference identifier (SRID). If an SRID value is provided, the returned geometry has this SRID value. Otherwise, the SRID value of the returned geometry is set to zero (0).

Return type

GEOMETRY

If wkt_string or srid is null, then null is returned.

If srid is negative, then null is returned.

If wkt_string is not valid, then an error is returned.

If srid is not valid, then an error is returned.

Examples

The following SQL constructs a geometry object from the WKT representation and SRID value. 

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

st_geomfromtext
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0103000020E61000000100000005000000000000000000000000000000000000000000000000000000000000000000F03F000000000000F03F000000000000F03F000000000000F03F000000000000000000000000000000000000000000000000