CREATE OR REPLACE FUNCTION dump_linestring_points(geometry)
  RETURNS SETOF geometry AS
$BODY$SELECT
	(
	'SRID=' ||
	bar ||
	';POINT(' ||
	foo ||
	')'
	)::geometry
FROM
	regexp_split_to_table(
		rtrim(
			substring(asewkt($1) from 23)
			,')'
		),
		','
	) as foo , srid($1) as bar
WHERE st_geometrytype($1)='ST_LineString';$BODY$
  LANGUAGE sql IMMUTABLE STRICT
  COST 1
  ROWS 100;