STNumCurves (geography Data Type)
Returns the number of curves in a one-dimensional geography instance.
Syntax
.STNumCurves()
Return Types
SQL Server return type: geography
CLR return type: SqlGeography
Remarks
One-dimensional spatial data types include LineString, CircularString, and CompoundCurve. An empty one-dimensional geography instance returns 0.
STNumCurves() works only on simple types; it does not work with geography collections like MultiLineString. NULL is returned when the geography instance is not a one-dimensional data type.
Null is returned for uninitialized geography instances.
Examples
A. Using STNumCurves() on a CircularString instance
The following example shows how to get the number of curves in a CircularString instance:
DECLARE @g geography;
SET @g = geography::Parse('CIRCULARSTRING(-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653)');
SELECT @g.STNumCurves();
B. Using STNumCurves() on a CompoundCurve instance
The following example uses STNumCurves() to return the number of curves in a CompoundCurve instance.
DECLARE @g geography;
SET @g = geography::Parse('COMPOUNDCURVE(CIRCULARSTRING(-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653))');
SELECT @g.STNumCurves();