I have a couple of questions with respect to creating a postal / 
zip code proximity search that is remotely accurate. The system I am 
using now is OK for small distances, but is terrible at calculating 
large distances.

   What I have is a database of establishments and their corresponding 
latitudes and longitudes, and I need to have users enter their own 
postal / zip code, and have the system calculate which establishments 
fall into a set range ($range) from their location. Not only does it 
need to find the establishments, it needs to calculate the distances 
(straight line, of course).

   Now, I have dug through the PHP archives, but there is no single 
clear explanation of how to do this, from beginning to end. I will 
start by putting down what I need, and then maybe other people can 
contribute to this and in the end we will have the solution, nice and 
tidy, in one place.

*** NOTE: I know doing this in PHP will be SLOW, but I do not want to 
write a MySQL user-defined function and recompile it and blah, blah, 
blah... (unless someone wants to cover that aspect!!! :D)

   Step 1: Take the postal / zip code that the user entered, and 
search the national postal / zip code database (which I already have) 
and return its corresponding latitude and longitude ($userLat and 

   Step 2: ???

   Step 3: Return the establishments information to the user, complete 
with the distances to them, ordered by smallest distance to largest.

If you can't help me out, maybe you can direct me to some online 
tutorials on this topic!

Thanks in Advance!
Brandon Pearcy
   Internet Technician

Bowes Online
  phone: 1-780-532-1110 ext. 265
  fax:   1-780-532-2120

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