ST_AsHEXEWKB
Name
ST_AsHEXEWKB — Returns a Geometry in HEXEWKB format (as text) using either little-endian (NDR) or big-endian (XDR) encoding.
Synopsis
    
     text
     
      ST_AsHEXEWKB
     
     (
    
    geometry
    
     g1
    
    , text
    
     NDRorXDR
    
    
     )
    
    ;
   
    
     text
     
      ST_AsHEXEWKB
     
     (
    
    geometry
    
     g1
    
    
     )
    
    ;
   
Description
Returns a Geometry in HEXEWKB format (as text) using either little-endian (NDR) or big-endian (XDR) encoding. If no encoding is specified, then NDR is used.
       
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       Availability: 1.2.2  | 
    
   
    
   
   This function supports 3d and will not drop the z-index.
  
   
    
   
   This method supports Circular Strings and Curves.
  
Examples
SELECT ST_AsHEXEWKB(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326));
		which gives same answer as
		SELECT ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326)::text;
		st_ashexewkb
		--------
		0103000020E6100000010000000500
		00000000000000000000000000000000
		00000000000000000000000000000000F03F
		000000000000F03F000000000000F03F000000000000F03
		F000000000000000000000000000000000000000000000000