ST_SetSRID
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Name

ST_SetSRID — Set the SRID on a geometry.

Synopsis

geometry ST_SetSRID(geometry geom, integer srid);

Descrizione

Sets the SRID on a geometry to a particular integer value. Useful in constructing bounding boxes for queries.

[Note]

This function does not transform the geometry coordinates in any way - it simply sets the meta data defining the spatial reference system the geometry is assumed to be in. Use ST_Transform if you want to transform the geometry into a new projection.

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

Questo metodo supporta le Curve e le Circular String.

Esempi

-- Mark a point as WGS 84 long lat --

SELECT ST_SetSRID(ST_Point(-123.365556, 48.428611),4326) As wgs84long_lat;
-- the ewkt representation (wrap with ST_AsEWKT) -
SRID=4326;POINT(-123.365556 48.428611)

-- Mark a point as WGS 84 long lat and then transform to web mercator (Spherical Mercator) --

SELECT ST_Transform(ST_SetSRID(ST_Point(-123.365556, 48.428611),4326),3785) As spere_merc;
-- the ewkt representation (wrap with ST_AsEWKT) -
SRID=3785;POINT(-13732990.8753491 6178458.96425423)