Posted by Iván Sánchez Ortega on 01/04/07 18:14

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bill wrote:

> Once I have the distance I need to sort the kennels by distance
> and present those within 500 miles.
[...]
> I ask for suggestions on the best approach.

First, do use MySQL's spatial extensions to store the lat-long coordinates
of every kennel.

Second, do use spatial operators to filter and sort by distance. It should
go like this:

select name,Distance(GeomFromText(''),kennels.position) as dist from kennels
where dist < 1500 sort by dist asc;

Easy, huh? I think that letting the hard work to MySQL is the fastest way.

However, you may run on a problem: the earth is flat, and calculating the
distance on the surface of a (quasi-)sphere is not trivial. You may
research on earth projection models (mercator, etc) to "flatten" out the
earth, so MySQL returns a nice cartesian distance.

> The kennel record has a row size of 1.118 bytes

Why? You can't change that or what?

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Iván Sánchez Ortega -ivansanchez-algarroba-escomposlinux-punto-org-

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