SqlGeography.STBuffer Method

Returns a geography object that represents the union of all points whose distance from a SqlGeography instance is less than or equal to a specified value.

Namespace:  Microsoft.SqlServer.Types
Assembly:  Microsoft.SqlServer.Types (in Microsoft.SqlServer.Types.dll)

Syntax

'Declaration
<SqlMethodAttribute(IsDeterministic := True, IsPrecise := False)> _
Public Function STBuffer ( _
    distance As Double _
) As SqlGeography
'Usage
Dim instance As SqlGeography
Dim distance As Double
Dim returnValue As SqlGeography

returnValue = instance.STBuffer(distance)

[SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)]
public SqlGeography STBuffer(
    double distance
)

[SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)]
public:
SqlGeography^ STBuffer(
    double distance
)

[<SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)>]
member STBuffer : 
        distance:float -> SqlGeography

public function STBuffer(
    distance : double
) : SqlGeography

Parameters

• distance
  Type: System.Double
  Is a double that specifies the distance from the geography instance around which to calculate the buffer.

Return Value

Type: Microsoft.SqlServer.Types.SqlGeography
A double that represents the union of all points that are the specified distance from the current SqlGeography.

Remarks

The STBuffer method calculates a buffer in the same manner as BufferWithTolerance, specifying tolerance = distance * .001 and relative = false.

A negative buffer removes all points within the given distance of the boundary of the SqlGeography instance.

Examples

The following example creates a LineString geography instance. It then uses the STBuffer method to return the region within 1 meter of the instance.

DECLARE @g SqlGeography;
SET @g = SqlGeography::STGeomFromText('LINESTRING(-122.360 47.656, -122.343 47.656)', 4326);
SELECT @g.STBuffer(1).ToString();

See Also

Reference

SqlGeography Class

Microsoft.SqlServer.Types Namespace