计算地球上两个坐标点之间距离的sql函数getDistance()

CREATE DEFINER = `root`@`localhost` FUNCTION `getDistance`(lng1 FLOAT,lat1,lng2 FLOAT,lat2 FLOAT) RETURNS DOUBLE
BEGIN
  DECLARE result DOUBLE;
	DECLARE radLng1 DOUBLE;
	DECLARE radLat1 DOUBLE;
	DECLARE radLng2 DOUBLE;
	DECLARE radLat2 DOUBLE;
	SET radLng1 = lng1 * pi() / 180.0;
	SET radLat1 = lat1 * pi() / 180.0;
	SET radLng2 = lng2 * pi() / 180.0;
	SET radLat2 = lat2 * pi() / 180.0;
	SET result = 2 * asin(sqrt(pow(sin((radLat1 - radLat2) / 2), 2) + cos(radLat1) * cos(radLat2) * pow(sin((radLng1 - radLng2) / 2), 2)));
	SET result = result * 6378.137;
	SET result  = ROUND(result * 100) / 100;
RETURN result;
END

计算方圆5公里的店铺：
SELECT * FROM 表名 WHERE getDistance(客户经度,客户纬度,longitude,latitude) < 5