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Andrew, there is a function called
proportionoverlap that will do this for you. You will use the SQL Select
statement. this will be a new column and you list it in the Select
Columns box. The syntax is "proportionoverlap(obj1,obj2)"
where obj1 is from the large region table and obj2 is your smaller region
table.
Select Columns - list the columns you want in
the final table along with your proportionoverlap(obj1,obj2) column
from Tables list your two tables
where condition 1st table.obj
intersects 2nd table.obj
you can also sort by using the 'order by column'
and the 'group by column'
This will return a area value for each small
region that intersects with the big region. I hope this helps.
Mike Hankins
Actuarial Services Analyst
Country Companies
----- Original Message -----
Sent: Monday, October 30, 2000 9:50
AM
Subject: MI-L Updating column with areas
from another table
Hello all,
I have one table with a lot of small regions and
one with two or three larger regions. I want to update a column in the 'larger
regions' table with the area of the smaller regions which are within the
larger regions (are you with me so far?). The update works fine except for the
fact that some of the small regions are only partially within the large
regions and don't get included. Is there any way of updating with only the
parts of the small regions which are actually inside the large regions without
having to use the 'set target / object split' option to permanently split the
smaller regions where they intersect the large regions.
<<...>>
Thanks
Andrew
Young
Durham City Council
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