Creates a polygon from a LineString and assigns it a spatial reference identifier (SRID).
Syntax
geometry ST_Polygon(geometry aLineString, integer srid)Parameters
| Parameter | Description |
|---|---|
aLineString | The closed LineString to build the polygon from. |
srid | The SRID to assign to the resulting polygon. |
Description
ST_Polygon returns a polygon built from the given LineString and sets its spatial reference system from the srid. It supports 3D geometries and preserves the z-index of the input.
MultiLineString is not accepted. Use
ST_LineMergeto merge its components into a single LineString.Polygons with holes are not supported. To create a polygon with holes, use
ST_MakePolygon.
Examples
Return EWKT output with SRID prefix.
SELECT ST_AsEWKT(ST_Polygon(ST_GeomFromText('LINESTRING(1 2,3 4,5 6,1 2)'), 4326));Output:
SRID=4326;POLYGON((1 2,3 4,5 6,1 2))What's next
ST_MakePolygon: Build polygons with holes or without an SRID assignment.
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