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_IsPolygonCW

ST_IsPolygonCW returns true if the 2D projection of the input polygon or multipolygon is clockwise. If the input geometry is a point, linestring, multipoint, or multilinestring, then true is returned. For geometry collections, ST_IsPolygonCW returns true if all the geometries in the collection are clockwise.

Syntax

ST_IsPolygonCW(geom)

Arguments

Return type

BOOLEAN

If geom is null, then null is returned.

Examples

The following SQL checks if the polygon is clockwise.

SELECT ST_IsPolygonCW(ST_GeomFromText('POLYGON((7 9,8 7,11 6,15 8,16 6,17 7,17 10,18 12,17 14,15 15,11 15,10 13,9 12,7 9),(9 9,10 10,11 11,11 10,10 8,9 9),(12 14,15 14,13 11,12 14))'));

 st_ispolygonccw
----------
 true