| title | description | author | ms.author | ms.date | ms.service | ms.subservice | ms.topic | ms.custom | f1_keywords | helpviewer_keywords | dev_langs | monikerRange | |||||
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STUnion (geometry Data Type) |
STUnion (geometry Data Type) |
MladjoA |
mlandzic |
08/03/2017 |
sql |
t-sql |
reference |
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|
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=azuresqldb-current || >=sql-server-2016 || >=sql-server-linux-2017 || =azuresqldb-mi-current || =fabric |
[!INCLUDE SQL Server Azure SQL Database Azure SQL Managed Instance FabricSQLDB]
Returns an object that represents the union of a geometry instance with another geometry instance.
.STUnion ( other_geometry )
other_geometry
Is another geometry instance to form a union with the instance on which STUnion() is being invoked.
[!INCLUDEssNoVersion] return type: geometry
CLR return type: SqlGeometry
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.
The following example uses STUnion() to 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(); The following example returns a GeometryCollection instance that contains a circular arc segment.
DECLARE @g geometry = 'CURVEPOLYGON(CIRCULARSTRING(0 -4, 4 0, 0 4, -4 0, 0 -4))';
DECLARE @h geometry = 'POLYGON((5 -1, 5 -3, 7 -3, 7 -1, 5 -1))';
SELECT @g.STUnion(@h).ToString();STUnion() returns a result that contains a circular arc segment because the instance that invoked STUnion() contains a circular arc segment.