根据经纬度求两点之间距离(mysql 函数)

 1 DROP FUNCTION IF EXISTS `getDistance`;
 2 DELIMITER ;;
 3 CREATE FUNCTION `getDistance`(
 4      lon1 float(10,7) 
 5     ,lat1 float(10,7)
 6     ,lon2 float(10,7) 
 7     ,lat2 float(10,7)
 8 ) RETURNS double
 9 begin
10     declare d double;
11     declare radius int;
12     set radius = 6378140; 
13     set d = (2*ATAN2(SQRT(SIN((lat1-lat2)*PI()/180/2)   
14         *SIN((lat1-lat2)*PI()/180/2)+   
15         COS(lat2*PI()/180)*COS(lat1*PI()/180)   
16         *SIN((lon1-lon2)*PI()/180/2)   
17         *SIN((lon1-lon2)*PI()/180/2)),   
18         SQRT(1-SIN((lat1-lat2)*PI()/180/2)   
19         *SIN((lat1-lat2)*PI()/180/2)   
20         +COS(lat2*PI()/180)*COS(lat1*PI()/180)   
21         *SIN((lon1-lon2)*PI()/180/2)   
22         *SIN((lon1-lon2)*PI()/180/2))))*radius;
23     return d;
24 end
25 ;;
26 DELIMITER ;