title: radius search by latitude / longitude
body: <p>I have found a bunch of answers for this question using mysql , but I wasn't able to convert anything into a query ms sql 2008 can use.  I have a longitude and latitude column for each row in the database.  I am going to have a latitude and longitude for where the user is.  I want to be able to find all rows that are within x miles from the user's latitude/longitude.  Also when trying to use other queries I found on SO I keep getting the error  -  <code>'pow' is not a recognized built-in function name.</code>  which is weird , because I'm pretty sure that I have used <code>pow</code> before in sql 2008.  Any help with this would be greatly appreciated.  So far this is the closest  could come up with.</p>
  
  <pre><code>select * from tbl_MyTable
  WHERE (
  POW( ( 69.1 * ( Longitude - @longitude ) * cos( @latitude / 57.3 ) ) , 2 ) + POW( ( 69.1 * ( Latitude - @latitude ) ) , 2 )
  ) &lt; ( 5 *5 );
  </code></pre>