ST_LineInterpolatePoint

Introduction: Returns a point interpolated along a line. First argument must be a LINESTRING. Second argument is a Double between 0 and 1 representing fraction of total linestring length the point has to be located.

Format: ST_LineInterpolatePoint (geom: geometry, fraction: Double)

SQL example:

SELECT ST_LineInterpolatePoint(ST_GeomFromWKT('LINESTRING(25 50, 100 125, 150 190)'), 0.2) as Interpolated

Output:

+-----------------------------------------+
|Interpolated                             |
+-----------------------------------------+
|POINT (51.5974135047432 76.5974135047432)|
+-----------------------------------------+