附近的人计算方法-----使用mysql脚本计算方法

附近的人计算方法

drop functionif exists getDistance;

DELIMITER $$ 

CREATEDEFINER=`root`@`localhost`FUNCTION`getDistance`(

     lon1float(10,7)

    ,lat1float(10,7)

    ,lon2float(10,7)

    ,lat2float(10,7)

)RETURNSdouble

begin

    declareddouble;

    declareradiusint;

    setradius = 6378140; #假设地球为正球形，直径为6378140米

    setd = (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;

    returnd;

end

$$

DELIMITER ;

selectgetDistance(116.3899,39.91578,116.3904,39.91576);