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Checking is a column in a table or a view is of type geometry or geography

· 109 days ago by Simon Greener

Sometimes, some things are simple and prosaic rather than clever and complicated.

Building solutions in TSQL requires one to build a prior collection of handy functions before one can be really productive.

Here is a function I use called isGeo which if provided the name of a table/view and a column name returns 1 (true) if the column exists and is of type geometry or geography.

USE [GISDB]  /* Replace this with the name of your database */
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

CREATE FUNCTION [dbo].[isGeo] (schema_name nvarchar(128), 
                               object_name nvarchar(128), 
                               column_name nvarchar(128))
RETURNS int
WITH EXECUTE AS CALLER, 
     RETURNS NULL ON NULL INPUT
AS
BEGIN
  DECLARE v_result int;
        SELECT v_result=1
		  FROM (SELECT sc.name as schema_name,
					   ta.name as object_name,
					   co.name as column_name,
					   ty.name as column_type,
					   'TABLE' as object_type
				  FROM sys.tables ta
					   JOIN sys.schemas sc ON sc.schema_id = ta.schema_id 
					   JOIN sys.columns co ON ta.object_id = co.object_id
					   JOIN sys.types ty   ON co.user_type_id = ty.user_type_id
				 WHERE ty.name IN ('geography','geometry')
				 UNION ALL
				SELECT sc.name as schema_name,
					   va.name as object_name,
					   co.name as column_name,
					   ty.name as column_type,
					   'VIEW' as object_type
				  FROM sys.views va 
					   JOIN sys.schemas sc ON sc.schema_id = va.schema_id
					   JOIN sys.columns co ON va.object_id = co.object_id
					   JOIN sys.types ty   ON co.user_type_id = ty.user_type_id
				 WHERE ty.name IN ('geography','geometry')
				) a
			WHERE a.schema_name = schema_name
			  AND a.object_name = object_name
			  AND a.column_name = column_name ;
	Return case when v_result is null then 0 else v_result end;
END;

Now, some tests…

-- Check an existing geometry column in a physical table
select dbo.isGeo('dbo','ADMIN','GEOM') as Result;
Result
1
-- Check an existing geography column in a View
select dbo.isGeo('dbo','vw_terminal','shape') as Result;
Result
1
-- Try again with a non-existing schema
select dbo.isGeo('simon','ADMIN','GEOM') as Result;
Result
0
-- Check action of "RETURNS NULL ON NULL INPUT" function option
select dbo.isGeo(NULL,'ADMIN','GEOM') as Result;
Result
NULL
-- Check again with connected schema provided by appropriate function
select dbo.isGeo(SCHEMA_NAME(),'ADMIN','GEOM') as Result;
Result
1

I hope this helps someone.

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Extracting geometry type string values from geometry/geography objects in SQL Server 2008 Spatial

· 164 days ago by Simon Greener

Ever needed to extract a textual description of all geometry types in a single geometry/geography in SQL Server 2008?

Recently I had cause to do so and created the following function that implements this need.

/*********************************************************************************
** @function    : Geometry_Type
** @precis      : Returns geometry type of passed in geometry as string.
** @description : Returns list of geometry types (from OGC STGeometryType function)
**                that describe the contents of the passed in geometry.
**                Any GeometryCollection is "exploded" to examine the geometry types
**                within it.
**                Geography objects can be processed by converting to geometry using
**                dbo.toGeometry() function.
** @example     : select dbo.geometry_type(geometry::STGeomFromText('POINT(0 1 2)',0));
** @param       : p_geom : the geometry object to be processed.
** @param_type  : p_geom : geometry
** @history     : Simon Greener, The Spatial DB Advisor, September 2009
** @copyright   : Licensed under a Creative Commons Attribution-Share Alike 2.5 Australia License. 
**                (http://creativecommons.org/licenses/by-sa/2.5/au/)
**/

USE [GISDB]  -- Change this to your database
GO

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

Create function [dbo].[geometry_type]( @p_geom geometry )
  Returns varchar(MAX)
As
Begin
  Declare
    @v_geomn        Int,
    @v_geometryType varchar(100),
    @v_return       varchar(MAX);
  Begin
    If ( @p_geom is NULL ) 
      return NULL;

    SET @v_GeometryType = @p_geom.STGeometryType();

    IF ( @v_geometryType <> 'GeometryCollection' )
      SET @v_return = @v_GeometryType
    ELSE
    BEGIN
	  SET @v_geomn  = 1;
	  SET @v_return = 'GeometryCollection';
	  WHILE ( @v_geomn <= @p_geom.STNumGeometries() )
	  BEGIN
	    SET @v_GeometryType = @p_geom.STGeometryN(@v_geomn).STGeometryType();
	    IF ( CHARINDEX(':' + @v_GeometryType,==@==v_return) = 0 )
		  SET @v_return = @v_return + ':' + @v_GeometryType;
		SET @v_geomn = @v_geomn + 1;
	  END
    END;
    RETURN @v_return;
   END;
End
GO

Now let’s test it against a selection of all possible geometry types

select dbo.geometry_type(geometry::STGeomFromText('
POINT(0 1 2)',0)) as gtype 
union all select dbo.geometry_type(geometry::STGeomFromText('
MULTIPOINT((0 0 0), 
(1 1 1), 
(2 2 2), 
(3 3 3))',0)) as gtype 
union all select dbo.geometry_type(geometry::STGeomFromText('
LINESTRING(0 0, 1 1)',0)) as gtype 
union all select dbo.geometry_type(geometry::STGeomFromText('
MULTILINESTRING(
(0 0,1 1,1 2),
(2 3,3 2,5 4))',0)) as gtype 
union all select dbo.geometry_type(geometry::STGeomFromText('
POLYGON(
(326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
(326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0))',0)) as gtype 
union all SELECT dbo.geometry_type(geometry::STGeomFromText('
MULTIPOLYGON(
((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
	(326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0)),
((321000.0 5450000.0,322000.0 5450000.0,321500.0 5451000.0,321000.0 5450000.0)))',0)) as gtype 
union all select dbo.geometry_type(geometry::STGeomFromText('
GEOMETRYCOLLECTION(
POINT(2 3 4),
LINESTRING(2 3 4,3 4 5),
POLYGON((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0)),
POINT(4 5))',0));

gtype
Point
MultiPoint
LineString
MultiLineString
Polygon
MultiPolygon
GeometryCollection:Point:LineString:Polygon

But what if I want to create a single string that describes all the geometries in a particular table?

Here is one way to do this via XML aggregation.

WITH geometry_Types AS 
(
SELECT distinct dbo.geometry_type(a.geom) as gtype
  FROM (select           geometry::STGeomFromText('
POINT(0 1 2)',0) as geom
		union all select geometry::STGeomFromText('
MULTIPOINT((0 0 0), 
(1 1 1), 
(2 2 2), 
(3 3 3))',0) as geom
		union all select geometry::STGeomFromText('
LINESTRING(0 0, 1 1)',0) as geom
		union all select geometry::STGeomFromText('
MULTILINESTRING(
(0 0,1 1,1 2),
(2 3,3 2,5 4))',0) as geom
		union all select geometry::STGeomFromText('
POLYGON(
(326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
(326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0))',0) as geom
		union all SELECT geometry::STGeomFromText('
MULTIPOLYGON(
((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
 (326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0)),
((321000.0 5450000.0,322000.0 5450000.0,321500.0 5451000.0,321000.0 5450000.0)))',0) as geom
		union all select geometry::STGeomFromText('
GEOMETRYCOLLECTION(
POINT(2 3 4),
LINESTRING(2 3 4,3 4 5),
POLYGON((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0)),
POINT(4 5))',0) as geom
	   ) a
)
SELECT (STUFF((SELECT DISTINCT ':' + a.gtype
                 FROM geometry_types a
                ORDER BY ':' + a.gtype
                FOR XML PATH(''), TYPE, ROOT).value('root[1]','nvarchar(max)'),1,1,'')
        ) as GeometryTypes;

GeometryTypes
GeometryCollection:Point:LineString:Polygon:LineString:MultiLineString:MultiPoint:MultiPolygon:Point:Polygon



Notice how the list is not unique. Here is one method of making it unique.

WITH geometries AS 
(
select           geometry::STGeomFromText('
POINT(0 1 2)',0) as geom
union all select geometry::STGeomFromText('
MULTIPOINT((0 0 0), 
(1 1 1), 
(2 2 2), 
(3 3 3))',0) as geom
union all select geometry::STGeomFromText('
LINESTRING(0 0, 1 1)',0) as geom
union all select geometry::STGeomFromText('
MULTILINESTRING(
(0 0,1 1,1 2),
(2 3,3 2,5 4))',0) as geom
union all select geometry::STGeomFromText('
POLYGON(
(326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
(326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0))',0) as geom
union all SELECT geometry::STGeomFromText('
MULTIPOLYGON(
((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
 (326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0)),
((321000.0 5450000.0,322000.0 5450000.0,321500.0 5451000.0,321000.0 5450000.0)))',0) as geom
union all select geometry::STGeomFromText('
GEOMETRYCOLLECTION(
POINT(2 3 4),
LINESTRING(2 3 4,3 4 5),
POLYGON((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0)),
POINT(4 5))',0) as geom
)
SELECT (STUFF((SELECT DISTINCT ':' + a.gtype
                 FROM ( select distinct t.token as gtype
                          from geometries a
                               cross apply 
                               dbo.Tokenizer(dbo.geometry_type(a.geom),':') as t 
                       ) a
                 ORDER BY ':' + a.gtype
              FOR XML PATH(''), TYPE, ROOT).value('root[1]','nvarchar(max)'),1,1,'')
            ) as GeometryTypes;

GeometryTypes
GeometryCollection:LineString:MultiLineString:MultiPoint:MultiPolygon:Point:Polygon



Finally, show how we can use the function with geography type data.

select dbo.Geometry_Type(
           dbo.MBR2GEOMETRY(147,-44,148,-43,4326).STDifference(
               dbo.MBR2GEOMETRY(147.4,-43.6,147.6,-43.2,4326) ).STUnion(
                   dbo.MBR2GEOMETRY(150,-44,151,-43,4326) ) ) as geogtypes;

geogtypes
MultiPolygon



I hope this function is useful to someone.

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Vectorising geometry objects in SQL Server 2008

· 165 days ago by Simon Greener

I demonstrated in this article the usefulness of having a vectorising function in one’s spatial database kitbag (there are GetVector functions in my CENTROID and GEOM packages – in particular the GetVector function is vital to the implementation of the algorithm in my CENTROID.SDO_CENTROID function).

So, I have also added one to my SQL Server 2008 kitbag.

This function, as against the PostGIS and Oracle implementation, does not use any object types due to limitations in the SQL Server 2008 TSQL system (my implementation deliberately does not use the CLR system).

USE [GISDB]  -- Change this to your database
GO

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE FUNCTION [dbo].[GetVector]( @====p_geom geometry )
  RETURNS @Vectors TABLE
   (sx float,
    sy float,
    sz float,
    sm float,
    ex float,
    ey float,
    ez float,
    em float)  
AS
Begin
  Declare
    @v_GeometryType varchar(1000),
    @ringn          int,
    @geomn          int,
    @first          int,
    @second         int,
    @geom           geometry,
    @start_geom     geometry,
    @end_geom       geometry;
  Begin
    If ( @p_geom is NULL ) 
      return;

    SET @v_GeometryType = @p_geom.STGeometryType();

    If ( @v_GeometryType in ('Point','MultiPoint') ) 
      return;

    IF ( @v_GeometryType = 'LineString' )
    BEGIN
      SET @first  = 1;
      SET @second = 2;
      WHILE ( @second <= @p_geom.STNumPoints() )
      BEGIN
        SET @start_geom = @p_geom.STPointN(@first);
        SET @first      = @first  + 1;
        SET @end_geom   = @p_geom.STPointN(@second);
        SET @second     = @second + 1;
        INSERT INTO @Vectors ( [sx],[sy],[sz],[sm],[ex],[ey],[ez],[em] ) 
               VALUES ( @start_geom.STX,==@==start_geom.STY,==@==start_geom.Z,==@==start_geom.M,
                          @end_geom.STX,  @end_geom.STY, @end_geom.Z,   @end_geom.M );
      END;  
      RETURN;
    END;
    IF ( @v_GeometryType = 'MultiLineString' ) 
    BEGIN
      SET @geomn  = 1;
      WHILE ( @geomn <= @p_geom.STNumGeometries() )
      BEGIN
        SET @geom   = @p_geom.STGeometryN(@geomn);
        SET @first  = 1;
        SET @second = 2;
        WHILE ( @second <= @geom.STNumPoints() )
        BEGIN
          SET @start_geom = @geom.STPointN(@first);
          SET @first      = @first  + 1;
          SET @end_geom   = @geom.STPointN(@second);
          SET @second     = @second + 1;
          INSERT INTO @Vectors ( [sx],[sy],[sz],[sm],[ex],[ey],[ez],[em] ) 
               VALUES ( @start_geom.STX,==@==start_geom.STY,==@==start_geom.Z,==@==start_geom.M,
                          @end_geom.STX,  @end_geom.STY, @end_geom.Z,   @end_geom.M );
        END;
        SET @geomn = @geomn + 1;
      END; 
      RETURN;
    END;
    IF ( @v_GeometryType = 'Polygon' )
    BEGIN
      SET @ringn  = 0;
      WHILE ( @ringn < ( 1 + @p_geom.STNumInteriorRing() ) )
      BEGIN
        IF ( @ringn = 0 )
          SET @geom = @p_geom.STExteriorRing()
        ELSE
          SET @geom = @p_geom.STInteriorRingN(@ringn);
        SET @first  = 1;
        SET @second = 2;
        WHILE ( @second <= @geom.STNumPoints() )
        BEGIN
          SET @start_geom = @geom.STPointN(@first);
          SET @first      = @first  + 1;
          SET @end_geom   = @geom.STPointN(@second);
          SET @second     = @second + 1;
          INSERT INTO @Vectors ( [sx],[sy],[sz],[sm],[ex],[ey],[ez],[em] ) 
               VALUES ( @start_geom.STX,==@==start_geom.STY,==@==start_geom.Z,==@==start_geom.M,
                          @end_geom.STX,  @end_geom.STY,  @end_geom.Z,  @end_geom.M );
        END;
        SET @ringn = @ringn + 1;
      END; 
      RETURN;
    END;
    IF ( @v_GeometryType = 'MultiPolygon' )
    BEGIN
      SET @geomn  = 1;
      WHILE ( @geomn <= @p_geom.STNumGeometries() )
      BEGIN
        SET @ringn  = 0;
        WHILE ( @ringn < ( 1 + @p_geom.STGeometryN(@geomn).STNumInteriorRing() ) )
        BEGIN
          IF ( @ringn = 0 )
            SET @geom = @p_geom.STGeometryN(@geomn).STExteriorRing()
          ELSE
            SET @geom = @p_geom.STGeometryN(@geomn).STInteriorRingN(@ringn);
          SET @first  = 1;
          SET @second = 2;
          WHILE ( @second <= @geom.STNumPoints() )
          BEGIN
            SET @start_geom = @geom.STPointN(@first);
            SET @first      = @first  + 1;
            SET @end_geom   = @geom.STPointN(@second);
            SET @second     = @second + 1;
            INSERT INTO @Vectors ( [sx],[sy],[sz],[sm],[ex],[ey],[ez],[em] ) 
                 VALUES ( @start_geom.STX,==@==start_geom.STY,==@==start_geom.Z,==@==start_geom.M,
                            @end_geom.STX,  @end_geom.STY,  @end_geom.Z,  @end_geom.M );
          END;
          SET @ringn = @ringn + 1;
        END; 
        SET @geomn = @geomn + 1;
      END; 
      RETURN;
    END;
    IF ( @v_GeometryType = 'GeometryCollection' )
    BEGIN
      SET @geomn  = 1;
      WHILE ( @geomn <= @p_geom.STNumGeometries() )
      BEGIN
        If Not ( @p_geom.STGeometryN(@geomn).STGeometryType() in ('Point','MultiPoint') ) 
        BEGIN
           INSERT INTO @Vectors ( [sx],[sy],[sz],[sm],[ex],[ey],[ez],[em] )
                SELECT [sx],[sy],[sz],[sm],[ex],[ey],[ez],[em]
                  FROM dbo.GetVector(@p_geom.STGeometryN(@geomn));
        END;
        SET @geomn = @geomn + 1;
      END;
      RETURN;
    END;
  End;
  RETURN;
End
GO

Testing

Here’s a bunch of tests.

select v.*
  from dbo.GetVector(geometry::STGeomFromText(
'LINESTRING(0 0 10 10, 1 1 10 20, 2 2 10 30, 3 3 10 40)',0)) as v;

sx sy sz sm ex ey ez em
0 0 10 10 1 1 10 20
1 1 10 20 2 2 10 30
2 2 10 30 3 3 10 40 

select v.*
  from dbo.GetVector(geometry::STGeomFromText(
'MULTILINESTRING((0 0,1 1,1 2),(2 3,3 2,5 4))',0)) as v;

sx sy sz sm ex ey ez em
0 0 NULL NULL 1 1 NULL NULL
1 1 NULL NULL 1 2 NULL NULL
2 3 NULL NULL 3 2 NULL NULL
3 2 NULL NULL 5 4 NULL NULL 

-- Ordinary polygon
--
select v.*
  from dbo.GetVector(geometry::STGeomFromText(
'POLYGON((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0))',0)) as v;

sx sy sz sm ex ey ez em
326000 5455000 NULL NULL 327000 5455000 NULL NULL
327000 5455000 NULL NULL 326500 5456000 NULL NULL
326500 5456000 NULL NULL 326000 5455000 NULL NULL 

-- Polygon with a hole
--
select v.*
  from dbo.GetVector(geometry::STGeomFromText(
'POLYGON((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
(326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0))',0)) as v;

sx sy sz sm ex ey ez em
326000 5455000 NULL NULL 327000 5455000 NULL NULL
327000 5455000 NULL NULL 326500 5456000 NULL NULL
326500 5456000 NULL NULL 326000 5455000 NULL NULL
326500 5455500 NULL NULL 326550 5455200 NULL NULL
326550 5455200 NULL NULL 326450 5455200 NULL NULL
326450 5455200 NULL NULL 326500 5455500 NULL NULL 

-- MultiPolygon With a hole
--
select v.*
  from dbo.GetVector(geometry::STGeomFromText(
'MULTIPOLYGON(((326000.0 5455000.0,327000.0 5455000.0,326500.0 5456000.0,326000.0 5455000.0),
(326500.0 5455500.0,326550.0 5455200.0,326450.0 5455200.0,326500.0 5455500.0)),
((321000.0 5450000.0,322000.0 5450000.0,321500.0 5451000.0,321000.0 5450000.0)))',0))  as v;

sx sy sz sm ex ey ez em
326000 5455000 NULL NULL 327000 5455000 NULL NULL
327000 5455000 NULL NULL 326500 5456000 NULL NULL
326500 5456000 NULL NULL 326000 5455000 NULL NULL
326500 5455500 NULL NULL 326550 5455200 NULL NULL
326550 5455200 NULL NULL 326450 5455200 NULL NULL
326450 5455200 NULL NULL 326500 5455500 NULL NULL
321000 5450000 NULL NULL 322000 5450000 NULL NULL
322000 5450000 NULL NULL 321500 5451000 NULL NULL
321500 5451000 NULL NULL 321000 5450000 NULL NULL



But what if you want the start and end of the vector to be geometry points?

-- Get as points
--
select geometry::Point(v.sx,v.sy,0).STAsText() as startPoint,
       geometry::Point(v.ex,v.ey,0).STAsText() as endPoint
  from dbo.GetVector(geometry::STGeomFromText(
'LINESTRING(0 0 10 10, 1 1 10 20, 2 2 10 30, 3 3 10 40)',0)) as v;

startPoint endPoint
POINT (0 0) POINT (1 1)
POINT (1 1) POINT (2 2)
POINT (2 2) POINT (3 3)



Finally, what if you want each vector to be represented as a single linestring and not a individual ordinates (sx,sy, …. ,ez,em)?

-- Get as linestring
--
select geometry::STGeomFromText(
'LINESTRING(' + 
CAST(v.sx as varchar(10)) + ' ' + CAST(v.sy as varchar(10)) + ',' + 
CAST(v.ex as varchar(10)) +' ' + CAST(v.ey as varchar(10)) + ')',0).STAsText() as vLine
  from dbo.GetVector(geometry::STGeomFromText(
'LINESTRING(0 0 10 10, 1 1 10 20, 2 2 10 30, 3 3 10 40)',0)) as v;

vLine
LINESTRING (0 0, 1 1)
LINESTRING (1 1, 2 2)
LINESTRING (2 2, 3 3)



I hope this is useful to someone.

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MBR to geography/geometry helper functions

· 165 days ago by Simon Greener

Oracle has a polygon geometry type (non-standard) called an optimized rectangle. To define one all one has to do is supply it with the lower-left and upper-right coordinates. This is a much easier thing to do than having to supply 5 coordinates in anti-clockwise order.

PostGIS also has a bunch of bounding box functions that also are useful for when working with rectangular polygons or minimum bounding rectangles (MBRs).

I have been playing around a lot, recently, with grid generation in SQL Server 2008 (more on this in another post). And, in doing so, I decided to code some functions that would return SQL Server 2008 geometry and geography polygon objects given the lower-left and upper-right coordinates of a minimum bounding rectangle.

Here they are.

USE [GISDB]  -- Change this to your database
GO

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE Function [dbo].[MBR2GEOGRAPHY] (
  @p_minx  float,
  @p_miny  float,
  @p_maxx  float,
  @p_maxy  float,
  @p_srid  Int )
  returns geography
As
Begin
  Return geography::STGeomFromText('POLYGON((' + 
                 CONVERT(varchar(100), CAST(@p_minx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_miny as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_maxx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_miny as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_maxx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_maxy as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_minx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_maxy as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_minx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_miny as DECIMAL(24,12))) + '))',
                 @p_srid);
End;
GO

CREATE Function [dbo].[MBR2GEOMETRY](
  @p_minx  float,
  @p_miny  float,
  @p_maxx  float,
  @p_maxy  float,
  @p_srid  Int )
  returns geometry
As
Begin
  Return geometry::STGeomFromText('POLYGON((' + 
                 CONVERT(varchar(100), CAST(@p_minx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_miny as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_maxx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_miny as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_maxx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_maxy as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_minx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_maxy as DECIMAL(24,12))) + ',' +
                 CONVERT(varchar(100), CAST(@p_minx as DECIMAL(24,12))) + ' ' + CONVERT(varchar(100), CAST(@p_miny as DECIMAL(24,12))) + '))',
                 @p_srid);
End;
GO

Testing

Testing is pretty easy. 

-- First, let's create a simple polygon geometry
--
select dbo.MBR2GEOMETRY(0,0,100,100,0).STAsText() as geomWKT;

geomWKT
POLYGON ((0 0, 100 0, 100 100, 0 100, 0 0)) 

-- Now, let's create a polygon with a hole
--
select dbo.MBR2GEOMETRY(0,0,100,100,0).STDifference(dbo.MBR2GEOMETRY(40,40,60,60,0)).STAsText() as geomWKT;

geomWKT
POLYGON ((0 0, 100 0, 100 100, 0 100, 0 0), (40 40, 40 60, 60 60, 60 40, 40 40)) 

-- Now let's create a multipolygon with a hole
--
select dbo.MBR2GEOMETRY(0,0,100,100,0).STDifference(dbo.MBR2GEOMETRY(40,40,60,60,0)).STUnion(dbo.MBR2GEOMETRY(200,200,400,400,0)).STAsText() as geomWKT;

geomWKT
MULTIPOLYGON (((200 200, 400 200, 400 400, 200 400, 200 200)), ((0 0, 100 0, 100 100, 0 100, 0 0), (40 40, 40 60, 60 60, 60 40, 40 40))) 

-- Finally, let's create a polygon with a hole using the mbr2geography function
--
select dbo.MBR2GEOMETRY(147,-44,148,-43,4326).STDifference(dbo.MBR2GEOMETRY(147.4,-43.6,147.6,-43.2,4326)).STAsText() as geogWKT;

geogWKT
POLYGON ((147 -44, 148 -44, 148 -43, 147 -43, 147 -44), (147.40000000596046 -43.599999994039536, 147.40000000596046 -43.200000002980232, 147.59999999403954 -43.200000002980232, 147.59999999403954 -43.599999994039536, 147.40000000596046 -43.599999994039536))



I hope someone finds these functions useful.

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