stisring-geometry-data-type.md

title	STIsRing (geometry Data Type)
description	STIsRing (geometry Data Type)
author	MladjoA
ms.author	mlandzic
ms.date	08/03/2017
ms.service	sql
ms.subservice	t-sql
ms.topic	reference
ms.custom	ignite-2025
f1_keywords	STIsRing_TSQL STIsRing (geometry Data Type)
helpviewer_keywords	STIsRing (geometry Data Type)
dev_langs	TSQL
monikerRange	=azuresqldb-current || >=sql-server-2016 || >=sql-server-linux-2017 || =azuresqldb-mi-current || =fabric-sqldb

STIsRing (geometry Data Type)

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

Returns 1 if a geometry instance fulfills the following requirements:

• It is a LineString instance.
• It is closed.
• It is simple.
• Returns 0 if the LineString instance does not meet the requirements.

For a geometry instance to be closed and simple, both STIsClosed() and STIsSimple() must return 1 when invoked on the instance. To determine the instance type of a geometry, use STGeometryType().

Syntax

  
.STIsRing ( )  

Return Types

[!INCLUDEssNoVersion] return type: bit

CLR return type: SqlBoolean

Remarks

This method returns null if the instance is not a LineString.

Examples

The following example creates a LineString instance and uses STIsRing() to test whether the instance is a ring.

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

See Also

STIsClosed (geometry Data Type)
STGeometryType (geometry Data Type)
STIsSimple (geometry Data Type)
OGC Methods on Geometry Instances