Compute the Frechet distance with optional densification thanks to the corresponding GEOS function frechetdistance - SELECT ST_FrechetDistance( 'LINESTRING (0 0, 50 200, 100 0, 150 200, 200 0)'::geometry, 'LINESTRING (0 200, 200 150, 0 100, 200 50, 0 0)'::geometry, 0.5);