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ST_Polygon - Amazon Redshift

Amazon Redshift will no longer support the use of Python UDFs after June 30, 2026. We will start enforcing it in phases. For more information on the details of Python end of life and migration options, see the blog post that was published on June 30, 2025.

ST_Polygon

ST_Polygon returns a polygon geometry whose outer ring is the input linestring with the value that was input for the spatial reference system identifier (SRID).

The dimension of the returned geometry is the same as that of the input geometry.

Syntax

ST_Polygon(linestring, srid)

Arguments

linestring

A value of data type GEOMETRY or an expression that evaluates to a GEOMETRY type. The subtype must be LINESTRING that represents a linestring. The linestring value must be closed.

srid

A value of data type INTEGER that represents a SRID.

Return type

GEOMETRY of subtype POLYGON.

The SRID value of the returned geometry is set to srid.

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

If linestring is not a linestring, then an error is returned.

If linestring is not closed, then an error is returned.

If srid is negative, then an error is returned.

Examples

The following SQL constructs a polygon with an SRID value.

SELECT ST_AsEWKT(ST_Polygon(ST_GeomFromText('LINESTRING(77.29 29.07,77.42 29.26,77.27 29.31,77.29 29.07)'),4356));
st_asewkt ------------- SRID=4356;POLYGON((77.29 29.07,77.42 29.26,77.27 29.31,77.29 29.07))