ST_AsEWKT
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Name

ST_AsEWKT — Ritorna la rappresentazione Well-Known Text (WKT) della geometria con incluso lo SRID.

Synopsis

text ST_AsEWKT(geometry g1);

text ST_AsEWKT(geometry g1, integer maxdecimaldigits=15);

text ST_AsEWKT(geography g1);

text ST_AsEWKT(geography g1, integer maxdecimaldigits=15);

Descrizione

Returns the Well-Known Text representation of the geometry prefixed with the SRID. The optional maxdecimaldigits argument may be used to reduce the maximum number of decimal digits after floating point used in output (defaults to 15).

To perform the inverse conversion of EWKT representation to PostGIS geometry use ST_GeomFromEWKT.

[Warning]

Using the maxdecimaldigits parameter can cause output geometry to become invalid. To avoid this use ST_ReducePrecision with a suitable gridsize first.

[Note]

The WKT spec does not include the SRID. To get the OGC WKT format use ST_AsText.
[Warning]

WKT format does not maintain precision so to prevent floating truncation, use ST_AsBinary or ST_AsEWKB format for transport.

Enhanced: 3.1.0 support for optional precision parameter.

Enhanced: 2.0.0 support for Geography, Polyhedral surfaces, Triangles and TIN was introduced.

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

Questo metodo supporta le Curve e le Circular String.

Questa funzione supporta le Polyhedral Surface.

Questa funzione supporta i Triangoli e le Triangulated Irregular Network Surfaces (TIN).

Esempi

SELECT ST_AsEWKT('0103000020E61000000100000005000000000000
                        000000000000000000000000000000000000000000000000000000
                        F03F000000000000F03F000000000000F03F000000000000F03
                        F000000000000000000000000000000000000000000000000'::geometry);

                   st_asewkt
--------------------------------
SRID=4326;POLYGON((0 0,0 1,1 1,1 0,0 0))
(1 row)

SELECT ST_AsEWKT('0108000080030000000000000060E30A4100000000785C0241000000000000F03F0000000018
E20A4100000000485F024100000000000000400000000018
E20A4100000000305C02410000000000000840')

--st_asewkt---
CIRCULARSTRING(220268 150415 1,220227 150505 2,220227 150406 3)