Re: Postal code radius searches

On Wed, 6 Feb 2002, Milo Hyson wrote:

> I've been struggling with this problem for a while now and I can't seem to
> find a solution. I have a postal-code database, currently populated with over
> 76,000 United States ZIP codes. Each record contains, among other things, the
> latitude and longitude for the postal code. I have a stored procedure that
> calculates the distance between any two points on the globe. I'm trying to
> figure out a fast way to locate all of the postal codes within an arbitrary
> radius of another postal code.

Have you looked at PostGIS?  I'm a couple of revisions behind but I seem
to remember something about distances from points etc.  The down side is
it is only good on PG 7.1.3 and an upgrade to 7.2 won't be happening for
awhile as the developers are off making money (working) right now.


Best,
Rod
--
                      Let Accuracy Triumph Over Victory

                                                       Zetetic Institute
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                                                         Marc Stiegler