select * from `location` where ( acos( sin(([#latitude#]*3.1415)/180) * sin((latitude*3.1415)/180) + cos(([#latitude#]*3.1415)/180) * cos((latitude*3.1415)/180) * cos(([#longitude#]*3.1415)/180 - (longitude*3.1415)/180) )*6370.996 )<=1;
原文：https://www.cnblogs.com/banywl/p/9528868.html