ST_ShortestLine

Description

Returns the 2-dimensional shortest line between two geometries. The line returned starts in geom1 and ends in geom2 . If geom1 and geom2 intersect the result is a line with start and end at an intersection point. The length of the line is the same as ST_Distance returns for g1 and g2.

Availability: 1.5.0

Examples

Shortest line between Point and LineString

SELECT ST_AsText(  ST_ShortestLine(
        'POINT (160 40)',
        'LINESTRING (10 30, 50 50, 30 110, 70 90, 180 140, 130 190)')
	) As sline;
---------------------------------------------------------
 LINESTRING(160 40,125.75342465753425 115.34246575342466)

Shortest line between Polygons

SELECT ST_AsText( ST_ShortestLine(
         'POLYGON ((190 150, 20 10, 160 70, 190 150))',
         ST_Buffer('POINT(80 160)', 30)
              ) ) AS llinewkt;
-----------------
LINESTRING(131.59149149528952 101.89887534906197,101.21320343559644 138.78679656440357)

See Also

ST_ClosestPoint , ST_Distance , ST_LongestLine , ST_MaxDistance