ST_IsRing - Amazon Redshift
SyntaxArgumentsReturn typeExamples

Amazon Redshift will no longer support the creation of new Python UDFs starting Patch 198. Existing Python UDFs will continue to function until June 30, 2026. For more information, see the blog post .

ST_IsRing

ST_IsRing returns true if the input linestring is a ring. A linestring is a ring if it is closed and simple.

Syntax

ST_IsRing(geom)

Arguments

geom

A value of data type GEOMETRY or an expression that evaluates to a GEOMETRY type. The geometry must be a LINESTRING.

Return type

BOOLEAN

If geom is not a LINESTRING, then an error is returned.

Examples

The following SQL checks if the specified linestring is a ring. 

SELECT ST_IsRing(ST_GeomFromText('linestring(0 0, 1 1, 1 2, 0 0)'));

st_isring
-----------
 true