P - point POINT(10 10) GEOMETRYCOLLECTION EMPTY mP - MultiPoint MULTIPOINT((10 10), (20 20)) GEOMETRYCOLLECTION EMPTY L - Line LINESTRING(10 10, 20 20) MULTIPOINT((10 10), (20 20)) L - closed LINESTRING(10 10, 20 20, 20 10, 10 10) MULTIPOINT EMPTY L - self-intersecting with boundary LINESTRING(40 40, 100 100, 180 100, 180 180, 100 180, 100 100) MULTIPOINT((40 40), (100 100)) mL - 2 lines with common endpoint MULTILINESTRING( (10 10, 20 20), (20 20, 30 30)) MULTIPOINT((10 10), (30 30)) mL - 3 lines with common endpoint MULTILINESTRING( (10 10, 20 20), (20 20, 30 20), (20 20, 30 30)) MULTIPOINT((10 10), (20 20), (30 20), (30 30)) mL - 4 lines with common endpoint MULTILINESTRING( (10 10, 20 20), (20 20, 30 20), (20 20, 30 30), (20 20, 30 40)) MULTIPOINT((10 10), (30 20), (30 30), (30 40)) mL - 2 lines, one closed, with common endpoint MULTILINESTRING( (10 10, 20 20), (20 20, 20 30, 30 30, 30 20, 20 20)) MULTIPOINT((10 10), (20 20)) L - 1 line, self-intersecting, topologically equal to prev case MULTILINESTRING( (10 10, 20 20, 20 30, 30 30, 30 20, 20 20)) MULTIPOINT((10 10), (20 20)) A - polygon with no holes POLYGON( (40 60, 420 60, 420 320, 40 320, 40 60)) LINESTRING(40 60, 420 60, 420 320, 40 320, 40 60) A - polygon with 1 hole POLYGON( (40 60, 420 60, 420 320, 40 320, 40 60), (200 140, 160 220, 260 200, 200 140)) MULTILINESTRING( (40 60, 420 60, 420 320, 40 320, 40 60), (200 140, 160 220, 260 200, 200 140))