Interpolate_Point
INTERPOLATE_POINT(Geometry g1, Geometry g2);
Alias: ST_INTERPOLATE_POINT
Interpolates the point in g2 onto the line given in g1 and returns measure M as a float.
The first argument g1 must be of type Linestring, LinestringZ, LinestringM, or LinestringZM.
The second argument g2 must be of type Point, PointZ, PointM, or PointZM.
Result type: float
Example:
SELECT INTERPOLATE_POINT(GEOMFROMTEXT('LINESTRINGM(0 0 0, 0 15 30)'), GEOMFROMTEXT('POINT(10 10)');
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col1
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20.000
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