I need to find the highest point of a 3D line. To do so I use
ST_ZMax to obtain the Z-coordinate of the highest point:
SELECT ST_ZMax(geom) FROM 3dlines;
How can I find the X- and Y-coordinates of this point?
2 ways to do it
1) use st_dumppoints and order by st_z
2) create a polygon above your linestring and use st_3dclosestpoint to find your highest point.
select the point where z = ST_ZMax(geom)