STCentroid (geometry Data Type)

Article
05/23/2023

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Returns the geometric center of a geometry instance that consists of one or more polygons.

Syntax

  
.STCentroid ( )

Note

To view Transact-SQL syntax for SQL Server 2014 (12.x) and earlier versions, see Previous versions documentation.

Return Types

SQL Server return type: geometry

CLR return type: SqlGeometry

Open Geospatial Consortium (OGC) type: Point

Remarks

STCentroid() returns null if the geometry instance is not a Polygon, CurvePolygon, or MultiPolygon type.

Examples

A. Computing the centroid of a Polygon instance

The following example uses STCentroid() to compute the centroid of a polygon``geometry instance:

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.STCentroid().ToString();

B. Computing the centroid of a CurvePolygon instance

The following example computes the centroid for a CurvePolygon instance:

 DECLARE @g geometry = 'CURVEPOLYGON(CIRCULARSTRING(0 4, 4 0, 8 4, 4 8, 0 4), CIRCULARSTRING(2 4, 4 2, 6 4, 4 6, 2 4))';  
 SELECT @g.STCentroid().ToString() AS Centroid