+----------------------------------------------+ mysql> SELECT ST_AsText(ST_LineInterpolatePoint(@ls1, .75)); +-----------------------------------------------+ | ST_AsText(ST_LineInterpolatePoint(@ls1, .75)) | +-----------------------------------------------+ | POINT(2.5 5) | +-----------------------------------------------+ mysql> SELECT ST_AsText(ST_LineInterpolatePoint(@ls1, 1)); +---------------------------------------------+ | ST_AsText(ST_LineInterpolatePoint(@ls1, 1)) | +---------------------------------------------+ | POINT(5 5) | +---------------------------------------------+ mysql> SELECT ST_AsText(ST_LineInterpolatePoints(@ls1, .25)); +------------------------------------------------+ | ST_AsText(ST_LineInterpolatePoints(@ls1, .25)) | +------------------------------------------------+ | MULTIPOINT((0 2.5),(0 5),(2.5 5),(5 5)) | +------------------------------------------------+ 

ST_LineInterpolatePoints()  is a MySQL extension to OpenGIS. This function was added in MySQL 8.0.24. 

• ST_PointAtDistance( ls , distance ) 

This function takes a LineString  geometry and a distance in the range [0.0, ST_Length( ls ) ] measured in the unit of the spatial reference system (SRS) of the LineString , and returns the Point along the LineString  at that distance from its start point. It can be used to answer questions such as which Point  value is 400 meters from the start of the road described by the geometry argument. 

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

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

•If the geometry argument is not a LineString , an ER_UNEXPECTED_GEOMETRY_TYPE  error occurs. 

•If the fractional distance argument is outside the range [0.0, ST_Length( ls ) ], an ER_DATA_OUT_OF_RANGE  error occurs. 

ST_PointAtDistance()  is a MySQL extension to OpenGIS. This function was added in MySQL 8.0.24. 

• ST_SymDifference( g1 , g2 ) 

Returns a geometry that represents the point set symmetric difference of the geometry values g1  and g2 , which is defined as: 

g1  symdifference g2  := ( g1  union g2 ) difference ( g1  intersection g2 ) 

Or, in function call notation: 

ST_SymDifference( g1 , g2 ) = ST_Difference(ST_Union( g1 , g2 ), ST_Intersection( g1 , g2 )) 

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

mysql> SET @g1 = Point(1,1), @g2 = Point(2,2); mysql> SELECT ST_AsText(ST_SymDifference(@g1, @g2)); +---------------------------------------+ | ST_AsText(ST_SymDifference(@g1, @g2)) | +---------------------------------------+ 

