Fastest Way to Find Distance Between Two Lat/Long Points

Question

I currently have just under a million locations in a mysql database all with longitude and latitude information.

I am trying to find the distance between one point a

Answer 1

   select
   (((acos(sin(('$latitude'*pi()/180)) * sin((`lat`*pi()/180))+cos(('$latitude'*pi()/180)) 
    * cos((`lat`*pi()/180)) * cos((('$longitude'- `lng`)*pi()/180))))*180/pi())*60*1.1515) 
    AS distance
    from table having distance<22;