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Forum Newbie
Group: Forum Members
Last Login: 10/14/2009 5:16:08 PM
Posts: 8,
Visits: 15
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Hi, i need help to use Teradata SQL function to calcuation a distance from point a to point b which are using Longitude and latitude.
Please helps...
thanks,
T-Nguyen
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Supreme Being
Group: Forum Members
Last Login: 9/19/2009 4:48:19 PM
Posts: 105,
Visits: 146
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I’m not sure whether you are asking for the formulas or just how to do it in SQL. Maybe you can provide the formula and how the data is represented and then someone could suggest a method.
My suggestion would be to write a UDF or create a UDT (User Defiend Type) that contains the earth coordinates. Then you can define the user defined methods (UDMs) that operate on that data type.
If you are just looking for the formulas you can google that and get all sorts of hits that might be useful to you.
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Forum Newbie
Group: Forum Members
Last Login: 10/14/2009 5:16:08 PM
Posts: 8,
Visits: 15
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Hi Supprem being,
i need both formular and replicate that into SQL. if you have some source of example, i able to clone that.
thanks,
T-Nguyen
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Supreme Being
Group: Forum Members
Last Login: 11/5/2009 4:40:02 PM
Posts: 717,
Visits: 466
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First you have to define "distance", because there are several ways to calculate this :-)
For the "great circle distance" (http://en.wikipedia.org/wiki/Great_circle) there's already a UDF at
http://www.teradata.com/DownloadCenter/Topic9248-144-1.aspx
Dieter
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