STCurveToLine (geography Data Type)
Returns a polygonal approximation of a geography instance that contains circular arc segments.
Applies to: SQL Server (SQL Server 2012 through current version), Azure SQL Database.
Returns a LineString instance for a CircularString or CompoundCurve instance.
Returns a Polygon instance for a CurvePolygon instance.
Return a copy of geography instances that do not contain CircularString, CompoundCurve, or CurvePolygon instances.
Unlike the SQL MM specification, this method does not use z-coordinate values in calculating the polygonal approximation. Any z-coordinate values present in the calling geography instance are ignored.
The following example returns a LineString instance that is a polygonal approximation of a CircularString instance:
DECLARE @g1 geography = 'CIRCULARSTRING(-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653)';
DECLARE @g2 geography;
SET @g2 = @g1.STCurveToLine();
SELECT @g1.STNumPoints() AS G1, @g2.STNumPoints() AS G2;