STInteriorRingN (geometry Data Type)
Returns the specified interior ring of a Polygongeometry instance.
Syntax
.STInteriorRingN ( expression )
Arguments
- expression
Is an int expression between 1 and the number of interior rings in the geometry instance.
Return Types
SQL Server return type: geometry
CLR return type: SqlGeometry
Open Geospatial Consortium (OGC) type: LineString
Remarks
This method returns null if the geometry instance is not a polygon. This method will also throw an ArgumentOutOfRangeException if the expression is larger than the number of rings. The number of rings can be returned using STNumInteriorRing().
Examples
The following example creates a Polygon instance and uses STInteriorRingN() to return the interior ring of the polygon as a LineString.
DECLARE @g geometry;
SET @g = geometry::STGeomFromText('POLYGON((0 0, 3 0, 3 3, 0 3, 0 0),(2 2, 2 1, 1 1, 1 2, 2 2))', 0);
SELECT @g.STInteriorRingN(1).ToString();