difference function
Returns a geometry that represents that part of geometry a that does not intersect with geometry b.
Syntax
difference( a, b )
Arguments
geometry → geometry
geometry → geometry
Example
geomToWKT( difference( geomFromWKT( 'LINESTRING(3 3 , 4 4 , 5 5)' ) , geomFromWKT( 'LINESTRING(3 3 , 4 4)' )) ) → returns LINESTRING(4 4, 5 5)