STUnion (geometry)#
Returns an object that represents the union of a geometry instance with another geometry instance.
Syntax#
.STUnion ( other_geometry )
Arguments#
other_geometry
Is another geometry instance to form a union with the instance on which STUnion() is being invoked.
Return type#
geometry
Remarks#
This method always returns null if the spatial reference IDs (SRIDs) of the geometry instances do not match. The result may contain circular arc segments only if the input instances contain circular arc segments.
Example#
Compute the union 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.STUnion(@h).ToString();