ST_Polygon
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Name

ST_Polygon — Creates a Polygon from a LineString with a specified SRID.

Synopsis

geometry ST_Polygon(geometry lineString, integer srid);

Descrizione

Returns a polygon built from the given LineString and sets the spatial reference system from the srid.

ST_Polygon is similar to ST_MakePolygon Variant 1 with the addition of setting the SRID.

, ST_MakePoint, ST_SetSRID

[Note]

This function does not accept MultiLineStrings. Use ST_LineMerge to generate a LineString, or ST_Dump to extract LineStrings.

Questo metodo implementa le OGC Simple Features Implementation Specification for SQL 1.1.

Questo metodo implementa la specifica SQL/MM. SQL-MM 3: 8.3.2

Questa funzione supporta il 3d e non distrugge gli z-index.

Esempi

Create a 2D polygon.

SELECT ST_AsText( ST_Polygon('LINESTRING(75 29, 77 29, 77 29, 75 29)'::geometry, 4326) );

-- result --
POLYGON((75 29, 77 29, 77 29, 75 29))

Create a 3D polygon.

SELECT ST_AsEWKT( ST_Polygon( ST_GeomFromEWKT('LINESTRING(75 29 1, 77 29 2, 77 29 3, 75 29 1)'), 4326) );

-- result --
SRID=4326;POLYGON((75 29 1, 77 29 2, 77 29 3, 75 29 1))