ST_Multi
Name
ST_Multi — Return the geometry as a MULTI* geometry.
Synopsis
    
     geometry
     
      ST_Multi
     
     (
    
    geometry
    
     g1
    
    
     )
    
    ;
   
Description
Returns the geometry as a MULTI* geometry. If the geometry is already a MULTI*, it is returned unchanged.
Examples
SELECT ST_AsText(ST_Multi(ST_GeomFromText('POLYGON((743238 2967416,743238 2967450,
			743265 2967450,743265.625 2967416,743238 2967416))')));
			st_astext
			--------------------------------------------------------------------------------------------------
			MULTIPOLYGON(((743238 2967416,743238 2967450,743265 2967450,743265.625 2967416,
			743238 2967416)))
			(1 row)