Go to content Go to navigation and search

Home

Current SQL Server Blog Articles

    SQL Server Spatial: Converting a LineString to COGO XML
    SQL Server Spatial: Creating (Multi)LineStrings geometries from COGO XML instructions
    New Version of Package of TSQL Spatial Functions
    Vectorize/Segmentize SQL Server 2012
    Coordinate Editing Functions for SQL Server Spatial
    Function to Scale a geometry object for SQL Server Spatial
    TSQL String Tokenizer Function for SQL Server
    geography/geometry to MBR helper functions
    generate_series for SQL Server 2008
    Extract Polygons from result of STIntersection in SQL Server Spatial
    Function to round ordinates of a SQL Server Spatial geometry object
    Extract elements of SQL Server Spatial geometry object
    Counting number of polygon rings SQL Server Spatial
    Filtering Polygon Rings in SQL Server Spatial
    Function to Move a geometry object in SQL Server Spatial
    Alternate Centroid Functions for SQL Server Spatial
    Function to Rotate geometry objects in SQL Server Spatial
    A GetVertices wrapper for DumpPoints in SQL Server 2008 Spatial
    Creating a Morton number Space Key generator for SQL Server
    Gridding a geometry or geography object (SQL Server Denali)
    On hinting spatial indexes
    Random Search Procedure (SQL Server 2008 Spatial)
    COGO: Converting (Google Earth) Formatted Longitude/Latitude points to decimal degrees (SQL Server)
    COGO: Convert Degrees, Minutes and Seconds values to Decimal Degrees
    COGO: DD2DMS Formatting a latitude/longitude decimal degree value
    COGO: Create point from bearing and distance
    COGO: Compute number of vertices required to stroke circle or circular arc
    COGO: Calculating the bearing between two points (SQL Server 2008 Spatial)
    COGO: Compute arc length subtended by angle centre of circle
    COGO: Compute chord length of segment of a circle (arc)
    COGO: Computing Arc To Chord (Arc2Chord) Separation
    COGO: Creating a stroked polygon from a circle's centre x,y and radius
    COGO: Finding centre and radius of a curve defined by three points: FindCircle function
    Identifying Tight Radius Curves sections within LineString geometry data
    Generating random point data for SQL Server 2008 Spatial
    New Presentation on Active (Searchable) Spatial Metadata for SQL Server 2008 Spatial and FreeText
    Checking is a column in a table or a view is of type geometry or geography
    Extracting geometry type string values from geometry/geography objects in SQL Server 2008 Spatial
    Vectorising geometry objects in SQL Server 2008
    MBR to geography/geometry helper functions
    Extracting geometry types from geometry/geography objects in SQL Server 2008
    Getting the number of coordinate dimensions of a geometry/geography object in SQL Server 2008
    A Dump Points Function for SQL Server 2008 Spatial
    toGeography and toGeography Conversion Functions for SQL Server 2008 Spatial
    Write text file with spatial data from SQL Server 2008
    Loading Shapefiles into Geography type column in SQL Server 2008
    Tip #6: Correcting invalid geometries
    Tip #5: Where or where has my little column gone
    Tip #4: What Coordinate System is that?
    Tip #3: What object is that?
    Tip #2: Spatial Indexing and Primary Keys
    Tip #1: SQL Server 2008 "Katmai" - Setting SRIDs

Search

    Browse

RSS / Atom

Email me

textpattern

Creative Commons License
All Blog Articles, Data Models and Free Source Code by Simon Greener, The SpatialDB Advisor is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

generate_series for SQL Server 2008

Monday April 09 2012 at 23:36

A few years ago I wrote an article about implementing the PostgreSQL function, generate_series, in Oracle. This function is really useful for when trying to write SQL/Functions that can be implemented across one or more databases with reasonable ease.

Here is the function implemented in SQL Server 2008:

  1. -- Connect to database holding generate_series
  2. --
  3. USE [GISDB] -- Change to your database
  4. GO
  5. -- Drop function if exists
  6. --
  7. IF EXISTS (SELECT *
  8.              FROM dbo.sysobjects
  9.             WHERE id = object_id (N'[dbo].[generate_series]')
  10.               AND OBJECTPROPERTY(id, N'IsTableFunction') = 1)
  11. DROP FUNCTION [dbo].[generate_series]
  12. GO
  13. --
  14. -- Now let's create it
  15. --
  16. CREATE FUNCTION [dbo].[generate_series] ( @p_start INT, @p_end INT, @p_step INT=1 )
  17. RETURNS @Integers TABLE ( [IntValue] INT )
  18. AS
  19. BEGIN
  20.     DECLARE
  21.       @v_i                 INT,
  22.       @v_step              INT,
  23.       @v_terminating_value INT;
  24.     BEGIN
  25.       SET @v_i = CASE WHEN @p_start IS NULL THEN 1 ELSE @p_start END;
  26.       SET @v_step  = CASE WHEN @p_step IS NULL OR @p_step = 0 THEN 1 ELSE @p_step END;
  27.       SET @v_terminating_value =  @p_start + CONVERT(INT,ABS(@p_start-@p_end) / ABS(@v_step) ) * @v_step;
  28.       -- Check for impossible combinations
  29.       IF NOT ( ( @p_start > @p_end AND SIGN(@p_step) = 1 )
  30.                OR
  31.                ( @p_start < @p_end AND SIGN(@p_step) = -1 ))
  32.       BEGIN
  33.         -- Generate values
  34.         WHILE ( 1 = 1 )
  35.         BEGIN
  36.            INSERT INTO @Integers ( [IntValue] ) VALUES ( @v_i )
  37.            IF ( @v_i = @v_terminating_value )
  38.               BREAK
  39.            SET @v_i = @v_i + @v_step;
  40.         END;
  41.       END;
  42.     END;
  43.     RETURN
  44. END
  45. GO

Now, let’s test this function.

  1. -- Simple increment by 1
  2. SELECT g.IntValue AS generate_series
  3.   FROM generate_series(2,4,1) g;
  4. -- Results
  5. generate_series
  6. 2
  7. 3
  8. 4
  9. -- Increment using Default value (1)
  10. SELECT g.IntValue AS generate_series
  11.   FROM generate_series(1,5,DEFAULT) g;
  12. -- Results
  13. generate_series
  14. 1
  15. 2
  16. 3
  17. 4
  18. 5
  19. -- Increase in steps of 10
  20. SELECT g.IntValue AS generate_series
  21.   FROM [generate_series] ( 100, 200, 10 ) g;
  22. -- Results
  23. generate_series
  24. 100
  25. 110
  26. 120
  27. 130
  28. 140
  29. 150
  30. 160
  31. 170
  32. 180
  33. 190
  34. 200
  35. -- Negative decrement
  36. SELECT g.IntValue AS generate_series
  37.   FROM generate_series(5,1,-2) g;
  38. -- Results
  39. generate_series
  40. 5
  41. 3
  42. 1
  43. -- Invalid test
  44. SELECT g.IntValue AS generate_series
  45.  FROM generate_series(4,3,1) g;
  46. -- Results
  47. generate_series
  48. -- Increment negative numbers
  49. SELECT g.IntValue AS generate_series
  50.   FROM generate_series(-4,-1,1) g;
  51. -- Results
  52. generate_series
  53. -4
  54. -3
  55. -2
  56. -1
  57. -- generate some dates
  58. SELECT CONVERT(VARCHAR(20),GETDATE() + sa.IntValue,112) AS dates
  59.   FROM generate_series(0,14,7) sa;
  60. -- Results
  61. dates
  62. 20120410
  63. 20120417
  64. 20120424
  65. -- Create some points
  66. SELECT f.id,
  67.        geometry::Point(f.x,f.y,0 /* SRID */ ).STAsText()  AS geom
  68.   FROM ( SELECT sa.IntValue AS id,
  69.                 ROUND(10000 * RAND(CHECKSUM(NEWID())) +  353880,2) AS x,
  70.                 ROUND(5000  * RAND(CHECKSUM(NEWID())) + 5404973,2) AS y
  71.            FROM dbo.generate_series(1,25,1) sa
  72.         ) f
  73. ORDER BY 1 ASC;
  74. -- Results
  75. id  geom
  76. 1 POINT (363011.9 5406135.94)
  77. 2 POINT (361741 5408272.44)
  78. 3 POINT (363844.43 5408793.59)
  79. 4 POINT (356034.42 5405077.86)
  80. 5 POINT (360968.83 5408948.45)
  81. 6 POINT (363247.97 5408120.85)
  82. 7 POINT (363265.25 5409078.93)
  83. 8 POINT (355839.57 5405431.12)
  84. 9 POINT (358031.78 5408748.88)
  85. 10  POINT (362166.17 5408519.15)
  86. 11  POINT (357931.48 5405419.99)
  87. 12  POINT (362586.12 5404990.02)
  88. 13  POINT (359782.46 5405622.41)
  89. 14  POINT (354394.21 5406409.27)
  90. 15  POINT (355763.87 5406505.26)
  91. 16  POINT (357572.38 5407954.41)
  92. 17  POINT (356033.02 5408066.5)
  93. 18  POINT (360874.83 5407605.39)
  94. 19  POINT (360484.8 5406577.3)
  95. 20  POINT (359978.63 5404987.73)
  96. 21  POINT (363641.33 5407022.35)
  97. 22  POINT (357245.02 5407018.61)
  98. 23  POINT (355047.11 5407032.75)
  99. 24  POINT (357383.37 5405070.77)
  100. 25  POINT (356912.68 5408711.83)
  101. -- Extract Points from a geometry
  102. SELECT sa.IntValue AS pointN,
  103.        a.geom.STPointN(sa.IntValue).STX AS x,
  104.        a.geom.STPointN(sa.IntValue).STY AS y
  105.   FROM (SELECT geometry::STGeomFromText('LINESTRING(0 0,1 0,1 1,2 1,2 2)',0) AS geom) a
  106.        CROSS apply
  107.        dbo.generate_series(1,a.geom.STNumPoints(),1) sa;
  108. -- Results
  109. pointN  x y
  110. 1 0 0
  111. 2 1 0
  112. 3 1 1
  113. 4 2 1
  114. 5 2 2

I hope this function is useful to someone.

Creative Commons License

post this at del.icio.uspost this at Diggpost this at Technoratipost this at Redditpost this at Farkpost this at Yahoo! my webpost this at Windows Livepost this at Google Bookmarkspost this to Twitter

Comment [4]

Simon,

Finally got a chance to look at this but haven’t taken it thru paces yet. It seems your editor is stripping the @
sign. The above function didn’t compile for me until I changed all the variables to have @ in front of them.

Regina · 20 November 2008, 18:36 · #

Regina,

Thanks for pointing out the lack of @ symbols. Yes, Textile was removing them: I have fixed this so all should now be well.

Simon

Simon · 20 November 2008, 22:22 · #

Hi Simon,

The above function looks promising, but I get syntax errors in SSMS – specifically, line 10, syntax error near ‘-=’

Is this line correct? ABS

Cheers,
Kevin

Kevin · 17 July 2009, 18:51 · #

Kevin,

Thanks for pointing out the problem which crept in because of Textpattern formatting. Now fixed. Thanks
Simon

Simon · 18 July 2009, 00:09 · #