This is the presentation I used at the Insights User Conference for a training session back in June 2012

1. Peter Horsbøll Møller
Senior Systems Engineer
Pitney Bowes Software

2. The Power of Spatial SQL in MapInfo Professional
Peter Horsbøll Møller
Senior Systems Engineer
June 15, 2012
Every connection is a new opportunity™

3. Workshop agenda
• In this workshop we will play around with the spatial SQL
capabilties of MapInfo Professional
• We will look at joining tables based on the spatial objects
• We will calculate size of parts of the spatial objects
• We will extract and insert parts into new tables
3

4. SQL Select
• Columns, expressions
• Tables
• Conditions
4

5. Joining via the spatial object
• Select the two tables
– Object will come from
first table
• Specify spatial
condition:
– Contains
– Within
– Intersects
– Partly Within
– Contains Part
– Entirely Within
– Contains Entire
5

6. Contains / Within
• Comparing the
Centroid!
• Order does matter
• Good with points
• A Contains C
• A Contains D
• B Contain A
• C Contains D
• C Within A
• D Within A
• B Within A
• D Within C
6

7. Intersects / Partly Within / Contains Part
• Comparing the entire
object!
• Order doesn’t matter
• A Contains Part B
• A Contains Part C
• A Contains Part D
• B Contain Part A
• B Contains Part C
• C Contains Part A
• C Contains Part B
• C Contains Part D
• D Contains Part A
• D Contains Part C
7

8. Contains Entire / Entirely Within
• Comparing the entire
object!
• Order does matter
• A Contains Entire D
• C Contains Entire D
• D Entirely Within A
• D Entirely Within C
8

9. Spatial operators
• Within/Contains
– Very fast
– Inprecise when working with other objects than points
• Intersects/Partly Within/Contains Part
– Slower then Within/Contains
– Should be used when comparing lines/polylines and regions
• Entirely Within/Contains Entire
– Slower then Within/Contains
– To be used if one object should be ”entirely within” the other
9

10. Specifying columns
• Pick the columns from
the ”Columns” list
• Create expressions
using the ”Functions”
list or type in some
functions manually
• Use aliases (”some
new name”) for
expressions
10

11. Exercise
• Join the two tables Cadastre and Urban_Area
• Join them using the Intersects operator
• Select these columns
– CADASTRE.AREA_NAME
– CADASTRE.LOT_NO
– URBAN_AREAS.NAME
• Add these functions and aliases:
– CartesianArea(CADASTRE.OBJ, "sq m") "Area_Cadastre”
– CartesianArea(URBAN_AREAS.OBJ, "sq m") "Area_UrbanArea"
11

12. Adding a overlap tolerance
• Overlap(obj1, obj2):
– Creates an object where
the two objects have a
common ”area”
• MapInfo Pro will create
this object and calculate
the area of it
• If this area is larger then
10 sq m, the intersection
will be used
12

13. Calculating area overlap
There are a number of ways to calculate the size of the
overlapping area:
• CartesianArea(Overlap(obj, obj), units)
– Uses the defined units
– Should be used for projected data (non Longitude/Latitude data)
• SpericalArea(Overlap(obj, obj), units)
– Uses the defined units
– Should be used for Longitude/Latitude data
• AreaOverlap(obj, obj)
– Uses the current units in MapInfo Professional
– Uses the SpericalArea calculation
13

14. Exercise
• Add a overlap tolerance by adding this to the condition:
– CartesianArea(Overlap(Cadastre.obj, Urban_Areas.obj), "sq m") >
10
• Try different tolerances
• How do you change the unit used?
14

15. Extracting spatial data
• By default MapInfo Professional takes the spatial object
from the first table in your query
• You can however add ”more” spatial objects to your
query thru the ”Column” field
• To see these extra columns you need to insert the result
into a new/another table
15

16. Adding an extra spatial column
• Add your extra spatial
object, can be an
expression
• Consider using an alias
• Note that the result still
will highlight the entire
area from the first table
16

17. Creating a new table
• You can consider
using the structure
from your first table
and just modify it to
match the columns in
your query
17

18. Inserting the query
• You need to do this thru the MapBasic window
• Show the MapBasic Window from the Options menu
• Write this:
Insert Into OverlapResult (AREA_NAME, LOT_NO, NAME, OBJ)
Select AREA_NAME, LOT_NO, NAME, OverlapObj From Query1
• Where
– OverlapResult is your new table
– OverlapObj is your spatial column alias
– Query1 is the name of yoru query
• And hit enter
• Make sure your new table hasn’t been added to the map as
that will slow it down – a lot!
18

19. Final result
19

20. Exercise
• Add a spatial column to your result
• Create a new table
• Insert the result into this new table using this:
Insert Into OverlapResult (AREA_NAME, LOT_NO, NAME, OBJ)
Select AREA_NAME, LOT_NO, NAME, OverlapObj From Query3
20

21. Regions and lines/polylines
• Works just like regions
and regions
• Note that Overlap uses
the style from the first
object
21

22. Exercise
• Find the roads that intersects the urban areas
• Use these columns from the roads:
– ROADNAME
– ROUTE_NO
– ID
• And this column from the urban areas
– NAME
• Extract only the part of the road within the urban area
• Create a new table
• Insert the result into this new table
Insert Into UrbanRoads (ROADNAME,ROUTE_NO,ID,NAME, OBJ)
Select ROADNAME,ROUTE_NO,ID,NAME, LineOverlap From Query1
22

23. Adding multiple spatial columns
• The SQL statement can include several spatial columns
23
Select Cadastre.LOT_NO
, Cadastre.AREA_NAME
, Cadastre.obj "CObj"
, Urban_Areas.obj "UObj"
, Overlap(Cadastre.obj
, Urban_Areas.obj) "JOBJ"
From Cadastre, Urban_Areas
Where Cadastre.Obj Intersects
Urban_Areas.Obj
into Selection

24. Extracting multiple spatial objects
• You need MapBasic to get to these ”many” spatial
columns
• They could be inserted into the cosmetic layer in this
way:
Fetch First From Selection
Dim oTemp As Object
oTemp = selection.UObj
Insert Into WindowInfo(FrontWindow(), 10) (OBJ) Values (oTemp)
24

25. Exercise
• Select multiple spatial columns
• Insert a few of the selected spatial data into the cosmetic
layer of a map window
25

26. Some other spatial function
• Overlap()
• Erase()
• Combine()
• IntersectNodes()
• ExtractNodes()
• MBR()
• Centroid()
• CreatePoint()
• CreateLine()
• Buffer() (Cart/Sper)
• Offset() (Cart/Sper)
• OffsetXY() (Cart/Sper)
• Rotate()
• RotateAtPoint()
26

27. Thank You
Peter Horsbøll Møller
peter.moller@pb.com