ST_InteriorRingN()

TL;DR

Use ST_InteriorRingN() to retrieve a one-based interior ring from a polygon.

Returns the interior ring at a one-based position in a polygon.

Syntax

ST_InteriorRingN(geom, n)

Arguments

Argument

Description

geom

A GEOMETRY or GEOMETRY32 polygon value.

n

The one-based interior-ring position (int64).

Return Value

Returns the same geometry precision type as geom.

Usage Notes

Examples

DROP DATABASE IF EXISTS geo_accessor_demo;
CREATE DATABASE geo_accessor_demo;
USE geo_accessor_demo;
SELECT ST_AsText(ST_InteriorRingN(ST_GeomFromText('POLYGON((0 0,10 0,10 10,0 10,0 0),(2 2,4 2,4 4,2 4,2 2))'), 1)) AS interior_ring;
DROP DATABASE geo_accessor_demo;

See Also

ST_NumInteriorRings, ST_ExteriorRing