makevalid-geometry-data-type.md

title	description	author	ms.author	ms.date	ms.service	ms.subservice	ms.topic	ms.custom	f1_keywords	helpviewer_keywords	dev_langs
MakeValid (geometry Data Type)	MakeValid (geometry Data Type)	MladjoA	mlandzic	08/03/2017	sql	t-sql	reference	ignite-2024	MakeValid MakeValid_TSQL	MakeValid (geometry Data Type)	TSQL

MakeValid (geometry Data Type)

[!INCLUDE SQL Server Azure SQL Database Azure SQL Managed Instance FabricSQLDB]

Converts an invalid geometry instance into a geometry instance with a valid Open Geospatial Consortium (OGC) type.

Syntax

  
.MakeValid ()  

Return Types

[!INCLUDEssNoVersion] return type: geometry

CLR return type: SqlGeometry

Remarks

This method may cause a change in the type of the geometry instance, as well as cause the points of a geometry instance to shift slightly.

Examples

The first example creates an invalid LineString instance that overlaps itself and uses STIsValid() to confirm that it is an invalid instance. STIsValid() returns the value of 0 for an invalid instance.

DECLARE @g geometry;  
SET @g = geometry::STGeomFromText('LINESTRING(0 2, 1 1, 1 0, 1 1, 2 2)', 0);  
SELECT @g.STIsValid();  

The second example uses MakeValid() to make the instance valid and to test that the instance is indeed valid. STIsValid() returns the value of 1 for a valid instance.

SET @g = @g.MakeValid();  
SELECT @g.STIsValid();  

The third example verifies how the instance has been changed to make it a valid instance.

SELECT @g.ToString();  

In this example, when the LineString instance is selected, the values are returned as a valid MultiLineString instance.

MULTILINESTRING ((0 2, 1 1, 2 2), (1 1, 1 0))  

The following example converts the CircularString instance into a Point instance.

DECLARE @g geometry = 'CIRCULARSTRING(1 1, 1 1, 1 1)';  
SELECT @g.MakeValid().ToString();  

See Also

STIsValid (geometry Data Type)
Extended Methods on Geometry Instances