ST_IsRing - Amazon Redshift
SyntaxArgumentsReturn typeExamples
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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
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 true