I have a point layer punkte_test. From that I want to make a line: first point of the line is the point A from the point layer itself. Second point of the line shall be y(B) = y(A) - 500 m . How can I realize that?
That's my idea:
SELECT ST_MakeLine(geom, concat(ST_X(geom), (ST_Y(geom)-500))) FROM liechtenstein.punkte_test
I use coordinate system UTM, so I want the second point to be 500 m south of A.