ST_MinimumClearanceLine — Returns the two-point LineString spanning a geometry's minimum clearance.
Geometry ST_MinimumClearanceLine(geometry 
			    g);
		Returns the two-point LineString spanning a geometry's minimum clearance.
        If the geometry does not have a minimum
		clearance, LINESTRING EMPTY is returned.
		
Performed by the GEOS module.
Availability: 2.3.0 - requires GEOS >= 3.6.0