ST_ForceCurve-ApsaraDB RDS(RDS)-阿里云帮助中心

Converts a geometry object to its curved representation.

Syntax

geometry ST_ForceCurve(geometry g);

Parameters

Parameter	Description
`g`	The geometry object to convert.

Description

ST_ForceCurve converts linear geometry types to their curve equivalents:

Line → CompoundCurve
MultiLineString → MultiCurve
Polygon → CurvePolygon
MultiPolygon → MultiSurface

If the input is already in curved representation, the function returns it unchanged.

The function supports 3D objects and preserves Z coordinates. It also supports circular strings and curves.

Example

SELECT ST_AsText(ST_ForceCurve(ST_GeomFromText('POLYGON((1 1,2 1,2 2,1 2,1 1))')));
              st_astext
-------------------------------------
 CURVEPOLYGON((1 1,2 1,2 2,1 2,1 1))
(1 row)