NYCPHP Meetup

[Rolan Yang]

Kshitij Bedi wrote:

>I have a database with zipcodes and corresponding latitudes and longitudes.
>Can anyone suggest a mysql statement that can pull me all zipcodes within 20
>or 50 or 100 miles of a given zipcode
>
>Kshitij Bedi 
>  
>

I did something like that a long time ago. Digging through my perl code,
I found this:

$ratio=0.0147791915; # miles per degree lattitude

Since the area that a zip code covers is somewhat of a fuzzy value, a
reasonable estimate would be to use something like this:

$dist=$miles*$ratio;
$query='select zipcodes from yourdatabase where 
lat>'.($currentlat-$dist).' and lat<'.($currentlat+$dist).' and 
lon>'.($currentlon-$dist).' and lon<'.($currentlon+$dist)';

you should obviuosly query the db beforehand to get the currentlat and 
currentlon based on your selected zipcode.

~Rolan