title: Optimize zipcode distance calculation
body: <p>Here is the question I have for all</p>
  
  <p>I already have an existing system that does the "Near By Zipcodes" search.</p>
  
  <p>The purpose of this post is to see if I can optimize the process.</p>
  
  <p>Currently, I have about 43k zipcode records.</p>
  
  <p>The way my current algorithm works is I select 1 record and do a full table scan of 43k records.</p>
  
  <p>Is there a way to only take a subset (lat range, long range) and do the calculation that way?</p>