0

我第一次使用其中一个，我很确定这可以工作，因为我已经在 Stackoverflow 上找到了它，但是当我将它作为 SQL 命令运行时它失败了。这似乎是一个常见问题，尝试了几组不同的代码后，我似乎遇到了同样的问题......

MySQL 说：

1064 - 您的 SQL 语法有错误；检查与您的 MySQL 服务器版本相对应的手册以获取正确的语法使用

在第 1 行的 '$$ CREATE FUNCTION GetDistance(coordinate1 VARCHAR(120), coordinate2 VARCHAR(') 附近

DROP FUNCTION IF EXISTS `GetDistance`$$
CREATE FUNCTION `GetDistance`(coordinate1 VARCHAR(120), coordinate2 VARCHAR(120))
    RETURNS VARCHAR(120)
BEGIN
    DECLARE pos_comma1, pos_comma2 INT;
    DECLARE lon1, lon2, lat1, lat2, distance DECIMAL(18,12);
    select locate(',', coordinate1) into pos_comma1;
    select locate(',', coordinate1, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate1, 1, pos_comma1-1) as DECIMAL(18,12)) into lon1;
    select CAST(substring(coordinate1, pos_comma1+1, pos_comma2-pos_comma1-1) as DECIMAL(18,12)) into lat1;
    select locate(',', coordinate2) into pos_comma1;
    select locate(',', coordinate2, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate2, 1, pos_comma1-1) as DECIMAL(18,12)) into lon2;
    select CAST(substring(coordinate2, pos_comma1+1, pos_comma2-pos_comma1-1) as DECIMAL(18,12)) into lat2;
        select ((ACOS(SIN(lat1 * PI() / 180) * SIN(lat2 * PI() / 180) + COS(lat1 * PI() / 180) * COS(lat2 * PI() / 180) * COS((lon1 - lon2) * PI() / 180)) * 180 / PI()) * 60 * 1.1515) into distance;
    RETURN distance;
END$$

谢谢 - 人族

编辑

试过了…………

DROP FUNCTION IF EXISTS `GetDistance`;
delimiter $$
CREATE FUNCTION `GetDistance`(coordinate1 VARCHAR(120), coordinate2 VARCHAR(120))
    RETURNS VARCHAR(120)
BEGIN
    DECLARE pos_comma1, pos_comma2 INT;
    DECLARE lon1, lon2, lat1, lat2, distance DECIMAL(18,12);
    select locate(',', coordinate1) into pos_comma1;
    select locate(',', coordinate1, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate1, 1, pos_comma1-1) as DECIMAL(18,12)) into lon1;
    select CAST(substring(coordinate1, pos_comma1+1, pos_comma2-pos_comma1-1) as DECIMAL(18,12)) into lat1;
    select locate(',', coordinate2) into pos_comma1;
    select locate(',', coordinate2, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate2, 1, pos_comma1-1) as DECIMAL(18,12)) into lon2;
    select CAST(substring(coordinate2, pos_comma1+1, pos_comma2-pos_comma1-1) as DECIMAL(18,12)) into lat2;
        select ((ACOS(SIN(lat1 * PI() / 180) * SIN(lat2 * PI() / 180) + COS(lat1 * PI() / 180) * COS(lat2 * PI() / 180) * COS((lon1 - lon2) * PI() / 180)) * 180 / PI()) * 60 * 1.1515) into distance;
    RETURN distance;
END;
$$

和..........

DROP FUNCTION IF EXISTS `GetDistance`;
$$
CREATE FUNCTION `GetDistance`(coordinate1 VARCHAR(120), coordinate2 VARCHAR(120))
    RETURNS VARCHAR(120)
BEGIN
    DECLARE pos_comma1, pos_comma2 INT;
    DECLARE lon1, lon2, lat1, lat2, distance DECIMAL(18,12);
    select locate(',', coordinate1) into pos_comma1;
    select locate(',', coordinate1, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate1, 1, pos_comma1-1) as DECIMAL(18,12)) into lon1;
    select CAST(substring(coordinate1, pos_comma1+1, pos_comma2-pos_comma1-1) as DECIMAL(18,12)) into lat1;
    select locate(',', coordinate2) into pos_comma1;
    select locate(',', coordinate2, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate2, 1, pos_comma1-1) as DECIMAL(18,12)) into lon2;
    select CAST(substring(coordinate2, pos_comma1+1, pos_comma2-pos_comma1-1) as DECIMAL(18,12)) into lat2;
        select ((ACOS(SIN(lat1 * PI() / 180) * SIN(lat2 * PI() / 180) + COS(lat1 * PI() / 180) * COS(lat2 * PI() / 180) * COS((lon1 - lon2) * PI() / 180)) * 180 / PI()) * 60 * 1.1515) into distance;
    RETURN distance;
END;
$$

两个都失败了......

人族

编辑 - 找到这个工作脚本....链接：http ://datamoil.blogspot.co.uk/2011/09/calculate-distance-between-two-points.html

CREATE FUNCTION distance_between (from_lat DECIMAL(6, 3), from_lng DECIMAL(6, 3), to_lat DECIMAL(6, 3), to_lng DECIMAL(6, 3)) RETURNS DECIMAL(11, 3)
RETURN 6371 * 2 * ATAN2(SQRT(POW(SIN(RADIANS(to_lat - from_lat)/2), 2) + POW(SIN(RADIANS(to_lng - from_lng)/2), 2) * COS(RADIANS(from_lat)) * COS(RADIANS(to_lat))), SQRT(1 - POW(SIN(RADIANS(to_lat - from_lat)/2), 2) + POW(SIN(RADIANS(to_lng - from_lng)/2), 2) * COS(RADIANS(from_lat)) * COS(RADIANS(to_lat))));
4

2 回答 2

1 
DROP FUNCTION IF EXISTS `GetDistance`;

delimiter $$
CREATE FUNCTION `GetDistance`...
   ...
   RETURN distance;
END;
$$
于 2012-04-29T13:42:52.813 回答
0

在执行此代码之前，您必须将分隔符更改为 $$。

这对我有用（在 MySql 上测试）

DROP FUNCTION IF EXISTS `GetDistance`;
delimiter $$
CREATE FUNCTION `GetDistance`(coordinate1 VARCHAR(120), coordinate2 VARCHAR(120))
    RETURNS VARCHAR(120)
BEGIN
    DECLARE pos_comma1, pos_comma2 INT;
    DECLARE lon1, lon2, lat1, lat2, distance DECIMAL(18,12);
    select locate(',', coordinate1) into pos_comma1;
    select locate(',', coordinate1, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate1, 1, pos_comma1-1) as DECIMAL(18,12)) into lon1;
    select CAST(substring(coordinate1, pos_comma1+1, pos_comma2-pos_comma1-1) as     DECIMAL(18,12)) into lat1;
    select locate(',', coordinate2) into pos_comma1;
    select locate(',', coordinate2, pos_comma1+1) into pos_comma2;
    select CAST(substring(coordinate2, 1, pos_comma1-1) as DECIMAL(18,12)) into lon2;
    select CAST(substring(coordinate2, pos_comma1+1, pos_comma2-pos_comma1-1) as DECIMAL(18,12)) into lat2;
    select ((ACOS(SIN(lat1 * PI() / 180) * SIN(lat2 * PI() / 180) + COS(lat1 * PI() / 180) * COS(lat2 * PI() / 180) * COS((lon1 - lon2) * PI() / 180)) * 180 / PI()) * 60 * 1.1515) into distance;
    RETURN distance;
END;
$$
于 2012-04-29T13:40:51.253 回答