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DuckDB function ST_InteriorRingN

Source: R/duckdb-funs.R
ST_InteriorRingN.Rd

Returns the N-th interior ring (hole) of a POLYGON as a LINESTRING. Indexing is 1-based (n = 1 returns the first interior ring). Returns NULL if the polygon is empty or has fewer than N interior rings.

Usage

ST_InteriorRingN(geom, n)

Arguments

geom

GEOMETRY

n

BIGINT

Value

GEOMETRY | LINESTRING_2D

Overloads

  • ST_InteriorRingN(geom = GEOMETRY, n = BIGINT)

  • ST_InteriorRingN(polygon = POLYGON_2D, n = BIGINT)

Provided by

The spatial extension (LOAD spatial;).

SQL examples

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));