STSymDifference (geometry Data Type)
Returns an object representing all points that are either in one geometry instance or another geometry instance, but not those points that lie in both instances.
Syntax
.STSymDifference (other_geometry)
Arguments
- other_geometry
Is another geometry instance in addition to the instance on which STSymDistance() is being invoked.
Return Types
SQL Server return type: geometry
CLR return type: SqlGeometry
Remarks
This method always returns null if the spatial reference IDs (SRIDs) of the geometry instances do not match.
Examples
The following example uses STSymDifference() to compute the symmetric difference of two Polygon instances.
DECLARE @g geometry;
DECLARE @h geometry;
SET @g = geometry::STGeomFromText('POLYGON((0 0, 0 2, 2 2, 2 0, 0 0))', 0);
SET @h = geometry::STGeomFromText('POLYGON((1 1, 3 1, 3 3, 1 3, 1 1))', 0);
SELECT @g.STSymDifference(@h).ToString();