show variables like '%func%';
set global log_bin_trust_function_creators=1;
use scm_wuliu
delimiter $$
create 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);