ST_LineInterpolatePoints(ls, fractional_distance)

This function takes a LineString geometry and a fractional distance in
the range (0.0, 1.0] and returns the MultiPoint consisting of the
LineString start point, plus Point values along the LineString at each
fraction of the distance from its start point to its endpoint. It can
be used to answer questions such as which Point values lie every 10% of
the way along the road described by the geometry argument.

The function is implemented for LineString geometries in all spatial
reference systems, both Cartesian and geographic.

If the fractional_distance argument divides 1.0 with zero remainder the
result may not contain the last point of the LineString argument but a
point close to it due to numerical inaccuracies in approximate-value
computations.

A related function, ST_LineInterpolatePoint(), takes similar arguments
but returns the Point along the LineString at the given fraction of the
distance from its start point to its endpoint.

ST_LineInterpolatePoints() handles its arguments as described in the
introduction to this section, with these exceptions:

o If the geometry argument is not a LineString, an
  ER_UNEXPECTED_GEOMETRY_TYPE
  (https://dev.mysql.com/doc/mysql-errors/8.0/en/server-error-reference
  .html#error_er_unexpected_geometry_type) error occurs.

o If the fractional distance argument is outside the range [0.0, 1.0],
  an ER_DATA_OUT_OF_RANGE
  (https://dev.mysql.com/doc/mysql-errors/8.0/en/server-error-reference
  .html#error_er_data_out_of_range) error occurs.

URL: https://dev.mysql.com/doc/refman/8.0/en/spatial-operator-functions.html

