ST_ExteriorRing()¶
TL;DR¶
Use ST_ExteriorRing() to retrieve a polygon’s outer ring.
Returns a polygon’s exterior ring.
Syntax¶
ST_ExteriorRing(geom)
Arguments¶
Argument |
Description |
|---|---|
|
A |
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_ExteriorRing(ST_GeomFromText('POLYGON((0 0,4 0,4 4,0 4,0 0))'))) AS exterior_ring;
DROP DATABASE geo_accessor_demo;