ST_GeometryType(g)

Returns a binary string indicating the name of the geometry type of
which the geometry instance g is a member. The name corresponds to one
of the instantiable Geometry subclasses.

ST_GeometryType() handles its arguments as described in the
introduction to this section.

URL: https://dev.mysql.com/doc/refman/8.0/en/gis-general-property-functions.html

