ST_MMin — Returns the M minima of a geometry.
float ST_MMin(geometry geom);
Returns the M minima of a geometry, or null of the geometry lacks M values.
该函数支持 3d 并且不会丢失 z-index。
此方法支持圆形字符串和曲线。
SELECT ST_MMin('POINT M (1 2 3)');
st_mmin
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3