ST_GeomFromEWKB — Devuelve un valor especifico de ST_Geometry desde una representación " Extended Well-Known Binary" (EWKB).
geometry ST_GeomFromEWKB(bytea EWKB);
Constructs a PostGIS geometry from an Extended Well-Known Binary (EWKB) representation.
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El formato EWKB no es un estándar del OGC, sino un formato especifico de PostGIS que incluye el identificador del sistema de referencia espacial (SRID) |
Mejora: 2.0.0 se introdujeron soporte de superficies poliédricas y TIN.
This function supports 3d and will not drop the z-index.
This method supports Circular Strings and Curves.
This function supports Polyhedral surfaces.
This function supports Triangles and Triangulated Irregular Network Surfaces (TIN).
This example constructs LINESTRING(-71.160281 42.258729,-71.160837 42.259113,-71.161144 42.25932) in NAD83 longitude/latitude (SRID 4269) from its EWKB representation.
PostgreSQL escape string syntax (E'...') always interprets backslash escapes. Each backslash therefore has to be doubled so that the bytea input parser receives the octal escapes.
SELECT ST_GeomFromEWKB((
E'\\001\\002\\000\\000\\040\\255\\020\\000\\000\\003\\000\\000\\000\\344\\112\\075' ||
E'\\013\\102\\312\\121\\300\\156\\303\\050\\010\\036\\041\\105\\100\\047\\277\\105' ||
E'\\047\\113\\312\\121\\300\\366\\173\\142\\235\\052\\041\\105\\100\\225\\174\\354' ||
E'\\056\\120\\312\\121\\300\\160\\231\\323\\145\\061\\041\\105\\100'
)::bytea);
0102000020AD10000003000000E44A3D0B42CA51C06EC328081E21454027BF45274BCA51C0F67B629D2A214540957CEC2E50CA51C07099D36531214540
With standard_conforming_strings enabled (the default), ordinary string literals preserve backslashes. The same EWKB can therefore be written with a single backslash before each octal byte value.
SELECT ST_GeomFromEWKB((
'\001\002\000\000\040\255\020\000\000\003\000\000\000\344\112\075' ||
'\013\102\312\121\300\156\303\050\010\036\041\105\100\047\277\105' ||
'\047\113\312\121\300\366\173\142\235\052\041\105\100\225\174\354' ||
'\056\120\312\121\300\160\231\323\145\061\041\105\100'
)::bytea);
0102000020AD10000003000000E44A3D0B42CA51C06EC328081E21454027BF45274BCA51C0F67B629D2A214540957CEC2E50CA51C07099D36531214540