附近的人计算方法drop function if exists getDistance;DELIMITER $$ CREATE DEFINER=`root`@`localhost` FUNCTION `getDistance`( lon1 float(10,7) ,lat1 float(10,7) ,lon2 float(10,7) ,lat2 float(10,7)) RETURNS doublebegin declare d double; declar
附近的人计算方法
drop function if exists getDistance;
DELIMITER $$
CREATE DEFINER=`root`@`localhost` FUNCTION `getDistance`(
lon1 float(10,7)
,lat1 float(10,7)
,lon2 float(10,7)
,lat2 float(10,7)
) RETURNS double
begin
declare d double;
declare radius int;
set radius = 6378140; #假设地球为正球形，直径为6378140米
set d = (2*ATAN2(SQRT(SIN((lat1-lat2)*PI()/180/2)
*SIN((lat1-lat2)*PI()/180/2)+
COS(lat2*PI()/180)*COS(lat1*PI()/180)
*SIN((lon1-lon2)*PI()/180/2)
*SIN((lon1-lon2)*PI()/180/2)),
SQRT(1-SIN((lat1-lat2)*PI()/180/2)
*SIN((lat1-lat2)*PI()/180/2)
+COS(lat2*PI()/180)*COS(lat1*PI()/180)
*SIN((lon1-lon2)*PI()/180/2)
*SIN((lon1-lon2)*PI()/180/2))))*radius;
return d;
end
$$
DELIMITER ;
select getDistance(116.3899,39.91578,116.3904,39.91576);
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